AppleInsider's Daniel Eran Dilger put together a lengthy five page review comparing iPhone to Palm's obsolete operating system, drawing comparisons to features, hardware, software design and usability. Guess who came out ahead? I'll give you a hint; it wasn't PalmOS.
Funny thing is, I was in the middle of writing an identical feature article for this site, some time ago, and gave up when I realized the entire topic was irrelevant because PalmOS (Garnet) is a dead, long forgotten platform that holds little interest for anyone these days. I would draw more interest by comparing iPhone to Mike Vick's ego.
Overall it's a good read, if you can spare 30 minutes of your lunch hour to digest it (the article, not your lunch). iPhone doesn't come out of this shooting match unscathed I'm afraid. Daniel makes no appologies for iPhones various weaknesses and shortcomings, like its maligned Mail app.