When Jack Lemmon and Walter Mathau made "Out to Sea," very late in their careers, and not very long before each passed away, it seemed that they were simply performing parts they could have "phoned-in," and perhaps add a few million dollars to their estates. Same for their original "Grumpy Old Men" flick, and even more so for its sequel. But a lot of that could be attributed to their ages, and to the fact that they had worked so much together - from earlier days through middle age and into their twilight time.
"Godfather III" was terrible, despite its two predecessors both winning "Best Picture" Oscar. And the recent "Spiderman," "Shrek" and "P.o.C." flicks certainly have all proved that in sequels, the third time certainly ISN'T the charm.
This movie seals that principle in concrete. With the ever-expanding ensemble cast, it's different from a two-person, buddy/rival offering like Lemmon/Mathau's or a larger, but somewhat-altered cast as in the Godfather movies. All the "Ocean" films have included the main group of hunky males and beautiful females, in their primes -- many of whom have been the "before-the-title" leads in their own individual work.
The problem is, the premise is exhausted; it's difficult enough to make one good major picture, and seemingly impossible replicate a third time (plus, the second/middle "Ocean" was even worse than this one).
But a main complaint, in my opinion, is that despite being younger, with flesh still firm on their faces and mid-sections, and without advancing age providing any excuse --- Clooney, Damon, Pitt, et al, seem to be performing barely a small notch above phoning in these roles, here. And the older Pacino and Gould almost seem to be attempting a parody of the roles they've been assigned, as opposed to straight acting. In terms of the plot, as another person commented here, it seems downright silly that the wise, caper-connected Gould character would be duped by the likes of Pacino's character in this story.
It might rate a 4* or 5* mark only -- I'd give it a 6, simply in view of excellent photography/scenery, and the lavishness of production.