In what way? What innovation is going on in the O/S world? What has changed radically over the last 5 years?

I used to care about the O/S, when you had little choice, when redhat was this small little sapling with a ton of things to do to get to windows. When macs were this weird other world that wasn't so unixy. When windows 95 came out and suddenly this whole new world opened up.

In those days, the O/S was the platform. Now, it's probably more important what browser you use than what O/S you use for most people.

But we're past all that now, an O/S is an O/S - there are a ton to choose from, they all do pretty much the same thing, and work the same(ish).

Now, the main aim for an O/S is to stay the heck out of the way IMHO.

There is A LOT of innovation going on in the O/S. Depressingly, not a lot of that truly revolutionary work is going on in the commercial/productized OS world.

Sun is doing great stuff with ZFS. Microsoft Research's Singularity is absolutely brilliant. Apple and Google are pushing mobile operating systems further than ever. I'm sure others could cite many more examples.