It never made sense to have Skype on a phone - with the cost of data and poor fidelity, the phone is superior because a call is cheaper and better. Maybe in places were data is competitive, maybe, but then, is it really worth it when all Skype does is turn a voice into inintelligible gibberish, and where you get to repeat everything fifteen times because it cuts out or sounds wierd.
MS has a long tradition of poor acquisitions - they pay large and reap little, and this is pretty much the case once again.
Microsoft isn't a one-trick pony like Google which only has one platform that comes to mind that could benefit from Skype integration, and Apple which already has a lackluster video-streaming service. Microsoft is the only corporation that comes to mind that has enough tributaries that would benefit from Skype integration: Windows Phone 7, Windows OS, Windows Tablet, Xbox Live, and Kinect.