The upgrades were okay. I couldn't stand the main character. Sure the conversation system looks like ME2 but when your options are some adjectives and not some actual written words there's no chance for that option that just catches your eye. The average person will just stick with what worked. ME2's scope also spans multiple games and A.P.s unpolished mechanics and really stupid protagonist (Stupid might not be the right word but he lacks a sense of presence. Shepard no matter what you picked had that.) really diminish any sense of scope. I didn't play very far but I was already bored of playing it.
Aspects of the conservation system annoyed me... when conversation is so important just having stances is a little vague, especially when the stances don't seem to reflect what is actually said. They called it suave, aggressive, professional after the 3 B's... Bond, Bauer and Bourne... yet in reality it was more "puerile humour, psychopath and completely generic neutral". I can't see Bond cracking jokes about people getting raped by polar bears... at least not without being incredibly subtle about it.
That said, the conversations in ME2 didn't seem to mean a whole amount. You got your paragon/renegade points, you got some additional information (that didn't really change the game) and with interrupts you could change your starting position in combat but on the whole the game was the same regardless. Even the "big moments" of keeping one characters loyalty were easy enough to either pass or immediately rectify. While seeing the consequences of your actions from the 1st game was enjoyable, again it didn't add a huge amount. Yes, seeing Wrex was cool... but you did the same missions regardless. The point extends to all of the cameos I can think of... none really changed the game and neither did most conversations. In contrast a single line choice in a single conversation in AP can affect everything that happens going deep into the game. Of pretty much any game I can think of in recent times, none have the choices and consequences that AP does... and I'm willing to forgive some of its flaws for that.
And that's the thing with replayability. There's lots of games out there where the choices you make in how
you play... ME2 is as good an example as any... different choices of class and even within a class powers lead to a different playing style. AP has that... but also has the fact that the game can radically alter on seemingly minor conversation choices, on the order you do missions (and not just in the cosmetic way other games deal with it) and the big choices genuinely are big choices that come back to haunt/help you rather than just give you morality points one way or the other.
If you could combine the production (which includes voice acting) and general sheen of ME2 (which is a great game in its own right) with the vision AP showed in a world of mundane RPGs that are churned out these days then I think we'd have had an RPG for the ages.
Which is why I'm hesitantly optimistic about New Vegas...