HTC Droid Eris
Not sure if there are 3rd party sync apps for it for the mac yet.
You can transfer files and pictures directly to the drive icon that shows up on the Mac desktop. It was hard for me to find my photos once I transferred them though. Once you've loaded the Camera you have to select the menu button on the screen to view any pictures you transferred to the SD card via the desktop.
Getting your contacts is a little trickier if you haven't already exported them to GMail. You'll want to go to your address book and highlight all contacts you want on the phone. Go to File and select Export and VCARDs. It's easiest to store them on the desktop. Then log into GMail, select the Contacts link, and then Import. Once that's successful your contacts should show up on the phone within 5 minutes.
I just got my Eris yesterday but can't figure how you got it to show up as drive. I plugged the usb into my MacBook Pro, tried connecting with bluetooth and the really strange part is i took the card out of the phone and put it in a card reader and no hard drive on the MacBook. Imported my contacts to gmail and setup iCal to sync to the gmail calendar and that works great. So far like the phone.