I tried N1 for a month. I really liked the Android OS. Lots of choices and freedom. The Android OS is like your parents are Hippies. iOS is like very loving yet over-protecting parents. There are pros and cos to both.
In the end of 30 day trial (in CA, you'll get 30-day return policy, elsewhere is 14 days.), I ultimately decided to return the phone mainly because some glitches/hardware flaws of some sort of the Nexus One. I'm still a fan of Android OS itself. Two biggest problems with N1 & Android 2.1 were the touch screen and wifi connectivity. Simply put, iPhone/iPad touch screen is really hard to beat (N1 has known problem with reversed multitouch registration and other issues). This could be purely hardware or could be fixed with Froyo, but they were too late to release it for N1. Also Wifi couldn't reconnect to my WPA secured networks after a while, and I had to manually tell the phone to reconnect so many times a day. This is most likely a software issue, but again, Froyo didn't come in time for me.
Android OS is getting better and better, and the competition is good for everyone. I'll evaluate Android phone in a year. Customer service from Google/HTC wasn't too bad. They even waived the restocking fees for me so the trial was entirely free for me. But it's really hard to beat Apple in this department. As long as I'm under warranty, I can just walk into Apple store and have the phone swapped right on the spot.
Just my $.02.