Personally, I believe the Uncharted Franchise should rest it's Multiplayer Mode in the next installment.
In Uncharted 2, we were given the first taste of Uncharted's Controls in a Multiplayer Format (IE: Really well) and in truth, the Upgradability of Uncharted 3's Multiplayer leaves no need for another Packaging of the same multiplayer, Either Create some form of New Game Plus for the MP stats, or give us a break from needing to buy 2 separate suites of DLC.
Both UC1 and UC2's Stories have had Setting based Coherency on an excellent scale, Uncharted 3 on the other hand smacked a little bit of what happened when the developers thought of grand setpieces in the usual "Hollywood Action Hero World Tour" but had to struggle to tie it all together, it all LOOKED awesome, and at the end of the day its still one of my favorite game series of this Console Generation....but it looks like the series could stand to back away from Multiplayer and put a little more length back into its story.