If you're serious about doing work, I'd still recommend a Blackberry. On AT&T you can get the Bold which:

• Has a real keyboard
• Takes care of email, calendars, tasks
• Will sync to your itunes library
• Is expandable via MicroSD
• Will allow you to carry a spare battery
• Has a flash and will record video
• Has a much better web browser than previous blackberries, though perhaps not quite as good as the iphone
• Has given me no dropped call or bluetooth issues
• Actually supports use as a tethered modem (I use mine as a tethered modem via bluetooth ALL the time). My understanding is that the iphone does not officially support this and the workarounds are a lot more cumbersome that launching the AT&T connection manager on your laptop and pressing "connect"
• The blackberry has some great apps of its own. Besides the standard google stuff (gmail, talk, calendar sync, maps) I use Garmin Mobile for Blackberry (to give voice prompted turn-by-turn navigation), Worldmate Live (to give me all of my flight, car, and hotel itineraries in one place, flight status notification, recommended alternates for when you need to be rerouted, etc), PodTrapper (to download all of my Podcasts over the air so I can always have the latest edition of Marketplace, Cartalk, Wait Wait, etc. Works great with the blackberry bluetooth stereo gateway - mounted it in my car so I have wireless playback of music and podcasts through the car stereo), Mileagetracker Pro (keeps track of my trips and then with a couple clicks will take my month's data, archive it on their web site, and email a report in PDF format to the office so I can get reimbursed). Has social networking apps like facebook & myspace for those who want them.
• Has a great speaker. It is actually loud and clear enough to set it on a table and use as a speakerphone or hear podcasts clearly

On the other hand, the eyephone has way more games.