For my taste, the more successful of the two was Duke Bluebeard's Castle—it would have been better titled Don't Go There—that Béla Bartók presented (if you can believe it) as a wedding present to his bride. I'd never seen it it live before, although I had seen a splendid (I suppose definitional) presentation by Solti with Hungarian singers on DVD.
You know the story: the bride wants Bluebeard to show her what is behind the doors: he tells her she'll regret it; she insists, and sure enough she regrets it. Willard White's Bluebeard was austere and remote, which worked. Elena Zhidkova as his bride was kittenish, which didn't seem to work so well. The the staging was a bit occult; Mrs. B. said she read it as a history of Russia which didn't sound like a bad guess.
But what made it was the orchestra: so far as I could discern there was simply no nuance of the score left unexplored. This has got to mean first-class conducting, which is to say Gergiev himself, who is also General Director and Artistic Director of the whole Mariinsky operation.
The other Mariinsky offering was Strauss' Die Frau ohne Schatten, The Woman without a Shadow, another that I had seen before only on DVD. This one was a bit less satisfactory, It's two parallel stories—one supernatural, one earthbound. And it was almost as if two different directors did the two different segments. The earthbound story was alive and full of energy, with so much emotional nuance you could almost follow the plot without a scorecard. The supernatural was vaporous—and the costumes appeared so heavy that you had to wonder how the singers dragged them around. The overall effect was Wagnerian and I do not mean that in a nice way. With only one prior viewing, I really don't know the opera well enough to venture whether the culprit is the current production or Strauss himself.
But once again, the sound from the pit was just superb. Strauss for me has taken some getting used to; not long ago I found him a chore (and indeed, I suspect he would not be a good place for a beginner to start his operatic inquiries). Still, sound like this makes you understand how wonderful the possibilities are. Gergiev's the man, and while you can see him a lot of places, the Mariinsky is the first place.