Currently Online 
I really don't see the Netflix difference at all and I have both systems hooked up next to each other and switch back and forth constantly. Custom backgrounds will be in the next update. I also switch between The Order 1886 theme and FFXIV theme both which have awesome background music to boot so a Wipeout pic is not really needed. Mp3 is half way there so far as you can use the USB music player feature. The only real feature that's missing at the moment is DLNA streaming but it's coming. (If you have Plex you can do it already)
As Kerotan already stated, compare it to the 2007 PS3. PS3 took a ton of time getting it's features back in the day. I can tell you one thing though, going from a DS3 to a DS4 controller is a dream! Not too mention no more rolling icons when trying to load trophies etc.
EDIT: Forgot my most cherished part of PS4. Game installing. Dragon Age Inquisition 45 GB install off the disk - 95 seconds. PS3 would probably take 95 minutes.
