don't the latest Call of Duties and Battlefield's have skill up's also? granted this brings up a good point, what components are needed for a game to be an RPG?
It certainly requires more than being able to add talent points to certain skill sets. To which we segue into...
Ohhh ohhh lets not forget Bioshock!
Love it, but completely linear, no quests, no ability to create a character. You can modify your abilities with talent points, and that's it. Doesn't count as a FPS/RPG hybrid IMO. Emphasis on a coherent plot does not make an RPG either.
I'd say an RPG requires a set of quests to be completed, some mandatory, others not. NPCs to interact with (talk, give quests, buy/sell/trade). There should be a rather in-depth inventory and skill system; the ability to either configure a party or personalize a character. Most of them have open world exploration of some type (like Final Fantasy and Mass Effect and Fallout 3).
They've already been used as examples, but hold Fallout 3 or Mass Effect (best FPS/RPG hybrids) up to Halo 3, CoD4 and Bioshock (premier FPSs of this past gen) and you can pretty clearly see where we can draw the line.