I too am wondering if this is a problem. I have a 3-year old MacBook Pro and just recently, it seems to be slowing down a little. Maybe 1 in 5 times I start it up, I get a gray screen with a BIG hard drive icon in the middle and an arrow under it. I have to click this arrow to proceed and all is well. But why is it suddenly doing this? Is it a sign that something is going to fail?

Forgot to mention... two months of warranty left. I think I'll be heading to the genius bar.