Well I just finished ME2, It took me more than a week to get through everything and I certainly enjoyed it. Naturally I plan to go through it again and get some of the other DLC packs (well mainly the Lair of the Shadow Broker) but I think I'll go through ME1 first and get a non-meta character imported this time.
Most of the problems I had with ME2 are quibbles and not really complaints. The only thing I actually didn't enjoy was the Hammerhead stuff, it just wasn't very interesting at all. I enjoyed how the missions, even the minor ones occurred in unique locations, but it seems like the unique and engaging environments were at the expense of variety and story telling. I suppose its something of a trade off, but I felt ME1, despite the numerous identical locales had a bit more bang-for-your-buck with its side quests. Especially with Admiral Hackett calling in to give you extensive background from time to time. ME2 also has some glitches and bugs, more so than I remember seeing in ME1, though nothing major. I guess my only personal regret, as I said, was using a meta-character import from the first game. Next time I wont input a Shepard that was created with a meticulously followed walk through.
As for what I enjoyed, I'd put the story at the top of the list. I thought the addition of "ammo" even if it makes zero sense in terms of story was a fine addition gameplay wise, I didn't think it detracted from anything. The dialogue was good and the acting as well was better than expected. I was impressed with how much more work was put into Joker, a relatively minor character from the first game with a few pivotal exploits. I didn't do any romance options this go-around, mainly because I thought none of the female alternatives were particularly attractive. Certainly I couldn't see Shepard with Miranda, anyone who wants to install a mind-control device in my brain is pretty much disqualified for intimate encounters. ME2 naturally ended much like the first game and I'm curious to see how this leads into the third installment, which sadly is still a long way off. Though perhaps not as far away as The Elder Scrolls V or Half Life 2: Episode 3.
Well I've rambled for long enough, the game was a good buy, more so since I got the Cerberus thing for free and I paid well under the 59.99 original price tag. And of course, what game can go wrong with Michael Dorn on the team anyway? Cheers!