Short version: This movie is dogshit. Nothing interesting happens, the screenplay is wall-to-wall formula, the action scenes are tepid, the whole production is shoddy and cheap-looking, the surprises are nonexistant, the acting is universally terrible. It's almost a perfect-disaster... a COMPLETE waste of time.
Ohterwise, let's take care of this in bullet-list form, because I'm too tired and annoyed to write flowery paragraphs.
- ALL the stuff that might be interesting: Wolverine's actual age, his birth name, his original identity, his real relationship to Victor "Sabretooth" Creed? His service in the Civil War, WWI, WWII and Vietnam? That's all zipped-through in the opening credits; about 5 to 10 minutes total. Rest of the film is a series of boring action scenes expanding on stuff we were already told in the first two (good) X-Men movies.
- For the record: It's every bit as bad as X3, probably much worse in some respects.
- Yes, there's lots of famous Mutants running around in the margins, but almost no one gets named or nicknamed. It's just weak fanservice to try and distract said fans from how shitty the movie is.
- Speaking of fans... holy shit, Marvel is going to be appologizing and/or "it wasn't us"-ing to Deadpool fans for YEARS after this. I can't remember the last time I saw a character THIS abused in a franchise film.
- The "explanation" for Wolverine's eventual amnesia is just about the dumbest thing thats ever been introduced into the X-Men movies, and I'm including the mutant-making machine in #1.
- Memo to Hugh Jackman: If you can't muster the enthusiam to act-in OR produce WELL a "Wolverine"/"X-Men" movie, step aside. I know, I know, every big actor needs a foundation to hold up the less profitable stuff he REALLY wants to do and Wolverine is the only character you've ever had boxoffice success with but... sorry, you're lack of interest is showing and you've produced and starred-in an utter turkey.
- It genuinely pains me to say this, but: Let this be the end of it. Fox clearly has no ability or inclination to make a good film in this series with a Bryan Singer around to steer the ship, so let it end now. Don't bother with further "origins" films, because it's now clear that they will suck. Let it go, let it die and hopefully let the rights revert back to Marvel who MIGHT be able to salvage this dead weight. Too bad, too.... TWO of these movies were friggin' great.
EDIT: By now, almost everyone has heard about the "multiple bonus scenes" business, i.e. that the final "stinger" scene after the credits differs from screen to screen (NOT the short scene that comes in the middle of the ending credits.) MOST people are seeing an ending setting up Wolverine being in Japan for the sequel (which at this point I'd be really surprised to see happen) but SOME prints are running with an alternate bit that's supposed to mitigate the (literal and figurative) butchering of Deadpool. The Deadpool stuff was, I'm told, NOT on the leaked work-print, so how much ya wanna bet THAT'S the "scenes that needed to be finished"?