Hermes is a Jamaican bureaucrat, not a diplomat! 
I haven't played The Simpsons Game yet......anytime something remotely mediocre involving The Simpsons comes out, people praise it to high heaven and I give it a look-see and it turns out that it sucks (see also: Simpsons Movie, random "good" episodes of New Simpsons from the last 6 years). The franchise has sunk to such awfulness that performances that are merely subpar get overhyped, so I am pretty wary of The Simpsons Game. It's like a 6-7 on most critics' scale, but take out The Simpsons and that probably sinks to a 5 or lower.
It's the best funny Simpsons content since the show went tits up. I'll confidently say that even after having watched the movie. You can read my impressions on my blog about the movie. Long story short: I thought it was mostly entertaining, and as good as a Simpsons movie could possibly be in the year 2007. I didn't think it was great, but there were some good bits in it.
The humor content in the Simpsons ia round the board pretty great, and sometimes even actually clever. Again, this is the Simpsons, and it is the year 2007, so it's not perfect, but I don't doubt this will be the best we get before they finally bury the franchise.
The reviews? I think they were a little harsh. Keep in mind that most reviewers only played the first few levels, which are by a wiiiiiiiiiiiiiiide margin the absolute worst, and least funny in the game. Around level 4 (there are like 14-15 levels), it picks up and turns on and stays pretty decent, even from a gameplay perspective. It's nothing groundbreaking or anything, but it's easy to play and really forgiving in difficulty (you always start right where you died, usually without a reload screen), so the few awful bits aren't awful for long.
But yeah, take out the Simpsons (including the humor) and the game is probably a 5. But with the Simpsons, and that humor, it's at least worth a rental playthrough. I guarantee the game will actually make you laugh at least once, which is more than I can say for like, any of the past 7 Simpsons seasons.
Did you ever play the Futurama game? I never finished it just because I got involved with other distractions, but I think the awful gameplay:funny dialogue ratio is enough not to make it a total waste. That's pretty much what I'd hope for with The Simpsons Game.....but it's EA, so they can probably do worse.
No, I never played the Futurama game. I heard it was sort of similar in quality, except the play in it was worse.
But yeah, tldr: The first 4 levels suck. Then it's mediocre-good but funny.
EDIT:
Also, Bender's Big Score > The Simpsons Game, mainly because Simpsons Game has a lil bit of suck involved (at the beginning) whereas Futurama is clean as long as you like, aren't allergic to fanservice.