Battery Life - The more you use it, the better it gets. I now get 2 days out of it, and I use the phone quite a lot, for games, music, web browsing.
Multi-Touch/Pinch Zoom - I personally don't see it as a necessity, good to have though.
Android 1.6 - Yeah, but it has lots of 2.X features,like Voice to search, etc. other than Live Wallpapers and more home screens, I dont see any difference in both versions. Then again, 2.1 is faster than 1.6. so maybe thats a plus.
cant delete email in bulk - yeah, that sucks.
cant send contacts without an app - I dont understand, just go into a contact, hit the menu button, and select send business card and it will send the contact via bluetooth, this is what I do, or do you mean something else?
cant delete items in timescape in bulk - yeah.
Playnow - works for me, but I disabled it manually, because it sucks, I dont know why you made this point as a negative.
Music Organiser - I personally love it, which one do you prefer?
I'm impressed with X10, it is the best looking phone on the market, also after using the HD2, I cant use any phone that its screen is less than 4". All what the X10 needs is software updates to fix little bugs, and add more features and optimization. other than that, the phone is good. enjoy your Desire, I find the Desire very ugly. I just cant stand it.