If my N900 lasts me 6 months at 900mhz, I'll be happy, since by then the exterior of the phone wil be pretty much trashed (yes, my N900 has a hard life).

I would be surprised if we don't see 1.5Ghz mobiles in the next year, so the point of the life expectancy of an overclocked 900 being only 3 years is a moot one to me.

Personally, I'm using the 900 a lot more for browsing now thats web pages load in a practical snap at 900mhz.