If you use iCloud, create a Shared Photo Stream album. This will sync automatically between your devices. You can even choose to share it with other iOS device users, who can contribute if you allow them to.
This is how I keep my wallpaper album, btw.
It's a bit of a pain in some ways, since you have to copy the image to Camera Roll, which puts in in the main Photo Steam, and then you have to share it to iCloud, where you select the album, then go back and delete it from Camera Roll and the main Photo Stream. But, strangely enough, I've started doing this for all my albums rather than syncing them through iTunes and the computer. Syncing across devices happens automatically, and if you make a mistake you can correct it on the iPad, or your other iOS devices.
The down side is you don't necessarily have copies on the computer.
But, back to the up side, the pictures aren't trapped on the device either. If something happens to your device, you just set up the new one with the same Apple ID, and you'll get your shared Photo Stream albums back. Cool?