Social networing overload?

Social Media and Networking seems to be the fastest growing sector on the internet these days.  So when is enough enough, and when does it become too much or overload?

I personally have 2 blogs on Blogger, 1 on Tumblr, 2 clients websites based on Word Press.  I maintain my own and a clients Twitter and Foursquare account as well as their Facebook page and my own Facebook account.  I have photo sharing accounts with Photobucket, Picasa and Instagram.
  I also use Google+, Orkut to connect with my Brazilian friends, LinkedIn to connect with business people, and also hold down a You Tube account.  I message through Skype and also have a Messenger account even if I haven't used it in ages.
  In the past I have also had accounts with Myspace and Bebo but these have been closed as they began to get less and less relevant.

So by my calculations I personally use 20 different social networking sites or accounts.  So is that overkill?  Is that normal? And while we're on it I use 5 different web browsers, Firefox, Opera, Chrome, Safari and when Im forced to by companies who are so far behind the times its not funny IE.

I may not be classed as part of the younger generation any more, but working in IT does necessitate the need to keep up with the times and the trends.  I have also found it great to meet so many people through twitter who even though I have never met, I have great conversations with even if they are limited to 140 characters.

I have also found twitter to be a great medium to keep up with people I have met on forums and websites, as well as keeping up to date with happenings on said websites, and other businesses that have kept up with the times and communicate with their customers and clients through this medium.

Another force in the industry has been the advance of smart phone and tablet technology and as an owner of two very modern smart devices from a well known and well capitalised company I have found these great platforms to interact with the world using these social networking tools, (Including checking in every time I go to the mall)

So I believe to stay up to the play with the modern world and the ever changing needs of a more mobile more connected society it is imperative to operate all these different accounts on these different networks, to not only keep myself abreast of developments and changes, but to keep up to date with the ways of the world and Gen Y.

I am interested to here your thoughts on all the different social networks out there, do you use a lot, some, 1 or 2?  Do you think Im over doing it having 20 different accounts? (remembering at least 4 are for clients)  Let me know what you think.