This is a discussion on Why should i root? within the Nexus One Development & Hacking forums, part of the Nexus One category; Originally Posted by SliceBurgSlim Free Wifi Tether and the AdFree Ad Blocker are a nice lil Bonus as well AdFree is the best! I was ...
I've been rooted since day one pretty much - i find the fact that I can do anything I want with my phone to be reason enough. I wrote a blog post here ( Nexus and beyond… - Adrian Cantrill's Blog ) about it... but should you want to have a poke around the N1 development community i'd suggest looking here ( Nexus One Android Development - xda-developers ).
If you want specific reasons
1) Undervolting (better power usage )
2) Overclocking (faster)
3) Himem (more memory - less lagg and stuttering )
4) APPS2SD (more storage)
5) Different Roms (again looksie Nexus and beyond… - Adrian Cantrill's Blog )
and about a million other reasons ... in short... do it