I have tried many iPhone Google Reader apps, and nothing has come close to working well for me but the web app as a web clip shortcut. That changed this week when I checked out Reeder (http://reederapp.com/2/)
I read a ton of Google Reader (usually 10,000+ posts a month) so I need something good. Reeder has actually replaced my Web Clip Reader link on my second iPhone page as my go to Google Reader app.
If you read a lot of feeds, from Google Reader, I suggest checking out Reeder.