I am one of those right tool for right job kind of people - when I need a phillips head screw driver I us a phillips head not a flat head screw driver or a hammer. The same goes for software.
I am getting awfully tired of hearing the refrain 'Why not use SharePoint?" when discussing enterprise social software. Don't get me wrong, I think that SharePoint is a great tool for certain things but unless you have a substantial IT budget to use for SharePoint, and lots of developers with SharePoint experience then SharePoint doesn't always foot the bill.
What is your experience and how have you overcome the Why not use SharePoint question?