I have played it and I will add my voice to those who say, "It's all meta-humor and actually good." Not great. It wasn't what I was expecting. But it was good. The whole thing is self-referential parody, and while enjoyable I find that those kind of set-ups are usually not as good as delivering a classic story well.
Nowhere does Bioware actually try to play this seriously. It is all meta-humor and character arc closure. At every point in the entire piece, which is nearly six to seven hours long, Bioware is intentionally mocking their own series and just letting the player see the characters with levity.
The dialogues are all comedic with sly references to the series' play style, strange dialog and character quirks, and false choices. For example, Clone!Shep pulls an "I should go," and then traps the entire party in an inescapable vault, and then Shep and crew actually talk for several lines about how awkward that was, complete with Shep trying different readings of the line. ("I should go. I *should* go. *I* should go.") Random NPCs are off-duty N7s who make off-hand comments about multiplayer play. Vorcha: ("Squad maybe good! Random group never good!") Traynor's toothbrush saves the day. For once Shepard says "All hands on deck for this one," and then you have to select the squad that actually goes with Shepard, though at least everyone else does come as well. The squad pulls an A-Team style "line-up and shoot the hell out of everything except their friend" moment. Twice, the mooks complain about how their boss is using them for cannon fodder while going off to finish last minute prep, highlighting how absurd that is to expect them to accept that. Then they go ahead and obey.
The character scenes are also used for humor and metahumor. EDI describes in detail Traynor's descriptions of what she wanted to do to EDI's "attractive" voice and gives her organic-synthetic extranet site links. Grunt amuses himself telling Shepard fans they can't see him/her. During an all-out firefight with every member of the crew present, they turn it into a snarky running competition about who took down the most enemies - exactly what people in real danger would not do but video game players would do. Shepard can serve as Garrus' wingman in the bar when he becomes awkward, and the scene shamelessly plays out like a beer commercial. Shepard's biggest grief with the Clone? He/she was going to throw out Boo, which causes Shepard to openly quote Minsc. ("Alright. Sit tight little fellow. Anybody gives you trouble, go for the eyes.") Traynor gets into a Tarantino-style showdown with her arch rival over a game of space-chess, needs a Shep-induced morale boost, then pulls an Ender's Game style win.
Even the death of the Clone was used for characterization. Shepard and the Clone are both about to fall off the Normandy's dock, and Shepard's allies unhesitatingly risk their lives to save Shepard. The Clone's allies do not. Earlier the villains had talked about "the cult of Shepard," and might as well have said it while staring at the camera. Likewise, during the Clone fight: (Clone: "My team is just as good as yours!" Shep: "You don't have a team. You have minions, and you're running out!")
There's a lot more of that kind of stuff. And you do not have to -like- this sort of thing. However, it was absolutely meant to be something other than a serious expansion to the game. I personally would have preferred a serious expansion, but I was laughing the whole time and enjoying it.