I don't think the Mac is dead yet. I just think 2011 will be the year of the Mac. I'm sure there is just a lot of new technology, like light cable, USB 3, better screens, bigger (in GBs) and less power hungry hard drives etc etc that are all on the horizon. And I'm sure Apple are taking the cautious approach of:
1. Making these technologies other technologies we don't yet know abput work 100% before putting then in their Mac product lines.
2. Making sure there is not too many big product releases in a year. Not everyone can afford every Apple product at one and Apple know this. So people already have to choose between iphone 4 and ipad. But if it was iphone 4 and ipad and new imac and new MBP and and . . . I think you get the issue. Stagnate the releases so people can save for (or slowly pay off) the Apple purchases they have made.
3. I think Apple have it harder this time round as they need to go back to the drawing board for 10.7 at least. Another Snow Leopard like updare for OS X will not cut it this time around. But the catch is 10.6 has almost everything we need to live our digital lives. All the basic things like backing up hard drives, setting up networks playing gams, writing letters, editing things etc etc we can to brilliantly with 10.6 (and software).
So it will take some time to think up and develop some new innovations for 10.7 And to be honest I really can't think anything new that 10.7 could use apart from touch screens technology or "Air Touch". Air Touch is my idea for a touch screen but instead of touching the screen you you your hand like a remote to move the things on your screen.
I think now is a turning point in computing. As the standard old idea of sitting your *** on a char and typing on a keyboard infront of a screen is becoming old and out dated. And it takes time to think of something to replace that, that is actually useful.