So you've heard about and maybe even registered for LinkedIn, Ryze, Ecademy, Soflow, or other networks. Why should you register for one and not another?
If you have unlimited time and the interest to do so, you could register for all of the services, then in each service you could create and maintain your profile, and maintain and grow your relationships. Doing so would be very time consuming.
So if your time is limited, you may want to register for each service and fill in minimal profile information for each service. This will enable people who know you to have a chance to search for you by name and find you in each service. With minimal profile information, people might not be able to find you by searching on keywords or other criteria besides your name. This would limit the value of each service, since people who you would want to contact you (such as a recruiter willing to give you a shot at your ideal job) might not be able to find you due to your minimal profile information.
So if you don't time to utilize each service to its maximum capabilities, but want to gain more value than minimal profiles alone can provide, then you'll probably want to pick one service as your primary network. In this primary network, you'll enter and maintain a complete profile and invite others to connect to you.
So which service should you pick as your primary service?
Well, obviously because this blog is about LinkedIn, you'll know my preference. Why do I chooose LinkedIn as my primary service? Here below are the major reasons. Please note that your circumstances and needs may vary wildly from mine, so these reasons may not be applicable or as important for you.
Contacts Already Registered in Service = Easier Connections
After joining a number of networks and filling in minimal profile information, I searched within each service to see who I could find was already registered in each network. Your experience may vary, but in my world of working in the high technology industry and going to both undergraduate and graduate school in Silicon Valley, I found that LinkedIn had by far the most people I knew registered already, more than all of the other networks combined (with the possible exception of Classmates.com, which is not suitable for professional purposes other than to find people you know by name).
For whatever network I chose, I wanted to connect to my trusted contacts in that network, so that they could give me introductions to their contacts that I didn't know. I figured that one factor for success in connecting to my trusted contacts would be if they were already registered for the service in which I was connecting to them. Since they were already registered with the service, I wasn't asking them to take the time to sign up for a new service, and they were already (at least a little bit) familiar with the service so it would take less effort for me to explain the benefits of connecting.
Who Do You Want to Meet?
Another factor in choosing LinkedIn was the quantity and quality of contacts there. When I search for various companies I admire, a search for high level titles such as CEO, VP, etc., or a search for people with skills and experience which intrigue me, I find more profiles of people whom I might like to contact in LinkedIn than in any other service.
So even if none of my trusted contacts were already in LinkedIn, I would have still picked LinkedIn as my primary network into which I would put a lot of effort because the opportunities for possible contacts are outstanding.
To take the point to an extreme, if most of my trusted contacts were using MySpace as opposed to LinkedIn, I don't think I would get more professional value out of MySpace because I had more trusted connections there. (Maybe this is because MySpace is a network in which vulgar language, images of scantily dressed people, and other non-professional content is shown prominently within many profiles. Not exactly a professional environment. I'm registered in MySpace, but have a minimal profile there.)
I don't pitch Soflow because there are so few people registered there compared to LinkedIn. As of today, LinkedIn has over three million users, while Soflow has 11,184. I don't get the impression that the quality of Soflow's users is so great that it overwhelms the quantity and quality of LinkedIn users.
openBC has less users and not as high of quality of users as LinkedIn (at least it appears that way to me). However, for those willing to register in more than network, I recommend openBC as a good secondary network because it appears to have many high-level professional contacts who are not available in LinkedIn. openBC has a global reach, but is particularly strong in its home country of Germany. While trying to find contacts at BMW's headquarters in Munich, I found many more relevant contacts within openBC than LinkedIn. But for all other projects, I have found LinkedIn to be useful and openBC to not be useful at all.
Ease of Use Important for Recruiting Trusted Contacts
When sending a request to someone within a network, it always helps to be introduced by a trusted contact. So it's important to recruit as many of your trusted contacts as you can into whatever network you choose as your primary network. It's easier to recruit a trusted contact when you can give them a demo of the service, and the demo doesn't turn them off.
So to recruit my trusted contacts, I make a sales pitch. This pitch must relay as quickly as possible the functionality and benefits of the service. I don't want to annoy or confuse my trusted contacts by pitching any other networks. So I make only one pitch, and that is for LinkedIn.
LinkedIn's interface communicates a professional image. This avoids turning off people who have no interest in getting involved with a network to make friends, chat, etc. This is important because most of my trusted contacts are not big Internet enthusiasts. Sure, they are computer saavy, but most have no interest in spending a lot of their free time in Yahoo! Groups, writing blogs, using RSS, joining Friendster, making friends online, etc. When I pitch LinkedIn, I make a pitch about how it can help them professionally. LinkedIn's UI and features reinforce my message.
Comparing LinkedIn's UI to Ryze and Ecademy, Ryze and Ecademy have interfaces which are ugly and unprofessional, in my opinion. Ecademy has so many features on its cluttered home page that it's overwhemling; I can't imagine most of my contacts taking the time to figure out how to navigate the site. Ryze, with its home page listing of "friends" and pictures, gives the impression that it's to be used like friendster, which is focused on making friends and dating. This would be a turn off to most of my trusted contacs.
openBC and Soflow both have pleasing and professional interfaces.
Summary and Conclusion
Because many of my trusted contacts were already registered in LinkedIn, I was initially drawn towards using LinkedIn as my primary network service. The quantity and quality of users registered with LinkedIn, and the professionalism of the site sealed the decision for me.
Your experiences and needs may vary from mine, so you may very well find that another service is more beneficial for you. Also, there are other factors that were not discussed above that may have an influence on your decision, including the functionality, privacy protection, and costs of each service.