You know, once upon a time I was always bothering about what's running in the background and what's using memory and all that. Totally micro-managing everything and stopping everything possible so there's no chance it would affect a game or whatever. That'd lasted for years and years - DOS, Win3, 95, XP... I could be really anal about the tiniest resource grab by apps or the OS.
Then I got a Core i7 and, frankly, I don't give a toss now. So long as I can't tell if anything is running, and it's not doing naughty stuff, I struggle to be bothered. In fact, just checking my task tray now I see 27 icons there, and there are a handful of gadgets on the desktop to boot. In a previous life that would horrify me! Fact is, PC hardware has just kept getting more powerful and capable faster than software is managing to soak it up. Apart from a few special cases where the developers really should be taken out and shot.