I have an eye-fi card for my Nikon dSLR. I copy the pics to my Tab, upload them to Picasa at full-res then delete from the Tab, and the still have them nicely in my gallery.

I still back up the pics to my computer and back-up drives from the eye-fi card when I get to a PC, but I find Picasa very handy.
ETA: I understand not everyone has either mobile or wifi access all the time. I use Amazon Mp3 but with both that and Google Music you can choose to download music to the device too, so you have it when you don't have reception- and you can rotate through which music you download. I'm going on a cruise, for example, and don't want to pay international roaming so I will download some things. but I don't have to store *everything* in my libraries on my phone/tab that way.