The Infuse is better...at least to me.
I was using a Blackberry Bold II/iPhone until last week. I had grown weary of waiting for the Galaxy S II so I broke down and grabbed an Infuse.
While I was fully prepared to be disappointed (I was VERY careful not to misplace the receipt, box, contents, etc.) I must say that despite one minor exception I haven't looked back for even a second.
Between the inflexible nature of the ios, and the apparent refusal/inability of RIM to produce a phone with top end specs, I decided that I wanted to see if there was something else out there that could fill the void.
The sheer size of the Infuse, some less than flattering reviews of the Atrix (from people who actually WORK at Motorola), and the still undetermined release date (at least as far as I know) of the GSII, all made the Infuse the easy choice.
As many have said, the choice is a vastly personal one, but I have to say that the Infuse has been (in my limited time with the unit) everything I had hoped for, and truth be told, much more than I realized was possible.
Take that for what it's worth, but once you start bumping around in Android land you will wonder how you were able to wander around in a fruit orchard for so long.
Good luck
GBA