So I've ordered a iPhone after the price drop and plan to switch to AT&T when it arrives. However, being on campus, I have nearly permanent access to WiFi as well as wireless from the 90 StarBucks in town. I don't really have a need for the data plan.

How should I go about doing this, if it's even possible.

Would the following work? That way I avoid a 2-year contract as well as a data plan.
1. Activating a new line at an AT&T store for my current unlocked V635 (which earns me the SIM). It will be the 39.99/450 plan.
2. Fake activation using the new SIM.

If this were to work, what would I lose without the data plan? I'm sure Visual Voicemail and YouTube are gone. Anything else?

i'm curious too... bump

you would only looks visual voicemail.
youtube can be activated thru installer, independence, etc.