Ok, I'm really going through a quandary right now as I am dealing with that same issue. except I currently own an iPhone 3gs. I am up for a new phone in the next week or so and I am debating if I want to stay with Apple and wait for the iPhone 5 or jump to Verizon and get the new Droid Bionic when it is released. Recently my best friend who is an Apple junkie made the jump over to an HTC Desire HD and he absolutely loves it. I have been a huge fan of my iPhone but after reading some things about the Bionic, it's making me think twice.
I didn't look into the same phones you are considering, but after comparing the Droids to the Verizon iPhone the decision really became a no brainer for me.
First, although I love iTunes, most of my music was not purchased through iTunes and what little was I upgraded to their DRM-free format. So that kind of negated the hassle of getting music onto my phone since I could just copy and past it onto a micro SD card.
Once the music issue was eliminated, the two things that really turned me off to the iPhone were the price and the fact that there is no removable storage. I already had a 16 gig memory card from a previous phone and I got an HTC Incredible with 8 gig of onboard memory for $50. Add that to my 16 gig card and I got a phone with 24 gig of memory for $50, vs $199 for a 16 gig iPhone.
I realize I'm a little behind the times with the Incredible, which is soon to be replaced, but I still feel like I got a good deal and we have a second line we're not currently using so I use that to get a new phone every year.
Oh, and perhaps the best part was, I sold my old phone (LG Chocolate Touch) for $75 on Amazon.com. Sounds like a lot of money, but for a buyer who broke theirs mid-contract it's still much cheaper than buying a new one.
So net of the net, I got PAID $25 to get a new phone.