Not up to BioWare's best, but a decent play nonetheless
The combat seems heavily borrowed from first person shooters, which is perhaps as it should have been. While it's certainly functional, it can be somewhat frustrating. For instance, when Commander Shephard "dies", the game ends. This is a step backwards from KOTOR, where when Revan dies, the other members can continue fighting (and at the end of the combat, everyone is revived).
Another gripe I have is the fact that there are what seems to be several steps backward in terms of how the role playing seems to be carried out. Personally, while it's amusing how you can choose various different ways to respond to various NPCs, and see different kinds of reactions, it seems to come at the price of your teammates.
In Baldur's Gate II, there were two things: banters, and interjections, that really added personality to each of your teammates. Occasionally, by random, two members of your party will speak to each other. Through these conversations, which are sometimes hilariously funny, sometimes painfully sad, sometimes very revealing, you learn a lot about the character of the people you travel with.
Other times, when you're speaking to an NPC, a party mate might interject with a comment. These interjections, too, reveal a character's ... well ... character. For some reason, BioWare toned both of these down. I could count the number of interjections I've seen on one hand. As for banters, they only occur during long elevator rides, and only occasionally.
Some might claim that interrupting gameplay for two team mates to talk to each other is disruptive to gameplay. If this were an FPS, I'd agree. But this isn't a first person shooter: although it has guns and can occasionally be played from a first person perspective, it's first and foremost an RPG. And as an RPG, such "interruptions" are not only not interruptions at all, but sometimes necessary to advance the character of the team mates.
In Baldur's Gate, having a party with the delicate elf Aerie and the brutish dwarf Korgan results eventually in a dual to the death between the two. You just couldn't have them both in the same party, because they WILL be at each other's throats. In life, as it should be in RPGs, such situations should be the case. Not for every character, of course, that'd be silly, but I was sad to see that you could put a Krogan with a Turian, and besides some acidic comments in an elevator, they're happy to work together throughout the whole game.
Ironically, I also feel that there just isn't enough dialog. I find that ironic because BioWare was careful to make sure everyone knew just how much of it was in Mass Effect (a lot, apparently). Yet despite that, I didn't get enough of a "feel" of my compatriots to really get close to them. For an example of a game that really got me close to characters, I would say FF7, or Baldur's Gate II, or especially Planescape: Torment.
Here in Mass Effect, i primarly see characters as vessels to hold talents, and not really as people I felt particularly deeply about. And before you say, "but you didn't play long enough with them", I played with Garrus (the Turian) from the moment I got him all the way to the end of the game. Twice. I still didn't really feel for the character beyond as a useful talent-holder.
I guess what disappoints me most about Mass Effect was that it was produced by a company that has produced better RPGs in the past. In my opinion, in terms of being an RPG (and ignoring other factors like graphics), KOTOR, Baldur's Gate II, and even Jade Empire were better. They were deeper, and the characters more in-depth. It just really seemed like BioWare was trying to appeal so much to the FPS crowd, they were leaving some of the RPG crowd in the dust.
Some people might say I'm being too hard on Mass Effect, but I feel that RPGs should be held to a higher standard than other game types. An FPS doesn't need a particularly strong storyline. Even if its story is absolute garbage, if it has cool and unique weapons, good collision detection, fun maps, good multiplayer, and good gameplay, then it doesn't matter as much.
But for an RPG, story is everything, and half of any story are the characters. If an RPG is a play, then the characters are the actors on the stage. And here, in Mass Effect, I feel it's like watching a play where great actors are hamstrung by lack of lines to say. It's a bit sad when NPCs BESIDES your team mates get more screen time than your team mates themselves, when it should be the other way around.
Now that I've finished bashing the things I don't like about the game, here's what I like about it:
The game's truly epic. You feel like you're in a huge universe, and the fate of that universe is on your shoulders.
The humans are not the top dogs of the universe. I love that. I hate games and movies (*ahem!* Star Wars *ahem!*) that just assume for some reason that humans are dominant. Here, we're the underdogs, trying hard to play galactic politics to get some leverage; any leverage.
The bad guy is truly awesomely evil. I love Saren as a villain, and I thought he was on par with Malak as a good foil to your character.
The graphics (despite annoying popping) are top-notch. The only gripe here is that apparently everything in the future is scrubbed with Spik & Span, because everything's so shiny.
When you DO get to talk to your team mates (not anywhere, as was the case with KOTOR and Baldur's Gate II, but only on the Normandy, and only after major events), the voicing is spot on, and the dialog engrossing and believable.
My final conclusion is that Mass Effect is a solid RPG. If you're into epic galactic romps this is the game for you. But while it's a great RPG, it's a far cry from BioWare's truly great creations. I'm still waiting for BioWare to make the equivalent of Baldur's Gate III, a game that truly caters to RPG fans and just RPG fans, that takes storytelling as its primary mission rather than an incidental one.