Aside from this article, Sling is killing themselves with crappy service.. I have 100 down and 10 up and sling buffers, gets blank screens ect... Going to dump it after this month and hope something else that actually works comes along..
I used to have many buffering problems with Sling, but their latest update solved most of them (possibly due to now pausing the feed when the channel bar is up). But I have noticed that ff through commercials in on-demand, never an easy task before, is near impossible now. It's almost guaranteed to lock-up if you try to go too fast, and of course if it does it means you cannot go back again without starting over. I'm sure that they did that to discourage commercial skipping.