"Any of the features on the phone" is simply not true. The only thing missing is the Play Store, and of course any attempts to sync, chat, email or locate friends using the Google apps fails (but that's what desired in this case). Everything else works perfectly.
You can still make calls, send SMSes, use the GPS, use the browser, and install as many third party apps as your heart desire. What else could you want? I know I didn't run into any other limitation.
The fact that Google requires an account to use for example Latitude or Gmail is not something you can hold against Android. They don't offer Gmail anonymously on any platform.