I'm playing through the Neverwinter Nights 2 expansion at the moment, since I've already completed Half-Life 2: Episode 2 (Manchester United 0) and I don't really want to get sucked back into Warcraft until the new expansion comes out (though I am quite tempted to take a look at some of the Hallow's End content, if only to get another Hallowed Wand that will allow me to transform party members into plaguebats or zombies).
I have a bit of an odd habit with RPG games. Because I'm basically the human equivalent of a five week old kitten, with an attention span to match, I like starting to play with things much more than seeing them through to a definitive conclusion, so it probably won't surprise you to hear that I've started playing most of the RPGs in my collection about thirty times each with different characters, but only rarely have I ever troubled the concluding couple of hours of them. (Baldur's Gate and the original Neverwinter Nights - plus its expansions - being rare exceptions)
Unsurprisingly, I started Mask of the Betrayer with about four different characters over the last week, which is probably testament to the fact that the first hour isn't as mind-numbingly dull as Irenicus's Dungeon in Baldur's Gate II (not that this ever stopped me from starting Baldur's Gate II two dozen times). That's not to say it's particularly interesting or exciting, just that it's passably enjoyable enough while I experiment with trying to find a decent combination of character classes that make my player character self-sufficient enough not to have to rest to recover their hit points every thirty steps.
Because Mask of the Betrayer is for Epic (i.e. Level 20-30 characters), it's rather on the hardcore side, meaning that you've really got to have a character that can wear heavy armour and hit things very hard, or be such a killer spellcaster that things will die pretty much as soon as you look at them, before they get into melee range and take you to pieces because you have no hit points and a poor armour class.
The Bard/Red Dragon Disciple I imported from my original NWN2 game didn't quite have the chops to cut it (a little light on spell power and hit points), thanks to the +2 level adjustment of being Drow. Trying to take on three or four level 20 spirit bears when you're only Level 17 is a bit much... So I restarted a couple of times until I settled on a combination I first tried and enjoyed in the original Neverwinter Nights - Fighter/Rogue. The Fighter levels give you the hit points and all the combat feats, whereas the Rogue levels give you lots of skill points, so you can disable traps (very important), open locks (less important, but still very useful) and top up your Diplomacy and Lore skills, so you have more conversation options and don't have to waste any money (or spell slots of NPCs) identifying high-end equipment. The only thing you really lack for true self-sufficiency is healing spells, but that's what you have health potions and healing kits for.
As for the game itself, I'm not really that far into it, but it is nice to get away from the Sword Coast, as the Forgotten Realms are a rather large place, and frankly, it's about time we got to see more of it. Not that this really makes a huge difference in the visual look of the game - the difference is more down to the politics and peoples of the region - especially the conflict and rivalry between the Rashemi and the Thayans. The cast (so far, at least) is also a little more untypical than the average computer-RPG, with a Red Wizard, a mind-reading Hagspawn and a death-obsessed Half-Celestial just for starters. They're a pretty serious bunch, (i.e. as straight-laced as a US Marine Corps Drill Sergeant's boots) but that's not necessarily a bad thing, assuming you found Grobnar and Co. as annoying as I did. It's a little disappointing that the game retreads a fair bit of ground covered by the first Neverwinter Nights expansion, Shadows of Undrentide, as there's a lot of plane-hopping going on to the Plane of Shadow, which just seems to be an excuse to use monochrome colour palettes that help disguise the continuing problems with the graphics engine.
The 3D camera in particular remains a hateful, schizophrenic thing - not knowing whether to be so sluggish as to totally kill your frame rate, or whether to be so overly sensitive that the merest touch of the mouse sends your view spinning through several hundred degrees. Graphics performance is barely improved over the original, and is shamed comprehensively by more sumptuous engines, such as the Episode 2-revamped Source. And the less said about the truly hideous and unfriendly GUI, the better...
It's still a bit early to call on the quality of the story and plot, but so far things look a little more promising, if anything thanks to the slightly more sober tone. The Forgotten Realms might be a weird and wonderful place - but I think they overplayed a lot of characterisation and quirkiness in the original. This seems a little more serious and is more in context of the harsh, unforgiving and tense history of the region the game takes place in. Like the original Neverwinter Nights before it, I can see myself completing the expansion pack long before I complete the main campaign of the game it spawned from, though thanks to the extended patching, I may actually go back to the original campaign and finish off the last act, just for completeness sake.
So, overall, it's okay. Not super-spectacular, but not super-bad either. If only they could sort out the graphics engine, I could imagine myself playing it a lot more. As it is, it's still got some way to go before it supplants Knights of the Old Republic as my favourite single-player RPG.