I'll speak to the opera offerings:

Figaro: What is more natural than Mozart in the city of his birth? The undisputed hit of last summer's Festspeile (when all 22 of Mozart's stage works were performed), this Figare was televised live to Europe on Opening Night. The production (by Claus Guth) is unique in that a non-singing character, "Cherubin" (sort of a doppleganger for Cherubino, a signing role) interacts with the main characters, "directing" the flow of the action (the DVD was just released in the US last week). Although Anna Netrebko is not singing Susanna this year, Diana Damrau is just as good (if not better, in some ways) : ) And unlike last year, when Harnoncourt conducted at super-slowwwww tempos, Daniel Harding should offer more reasonable tempos.

Onegin: Interesting cast (Mattei's first Onegin) and the best thing is the great Barenboim in the pit. The only thing is that the Grosses Festspielhaus is a real barn (not a huge number of rows, but a very very wide stage, so that seats in the extreme sides are not that good). However, it's the biggest venue, so more seats might be available.

Freischutz: Has the husband-wife team of Seiffert and Schnitzer - this opera has some truly great music with a sort-of- indecipherable plot (there are also some interesting supernatural elements in the second act as well).

Cellini: Uneven but still enjoyable Berlioz work with the up-and-coming Fritz in the title role and the great Kassarova as Ascanio. This looks like it will be a very modern "regie" production - don't expect lots of frill-and-lace sets and costumes! And with Gergiev in the pit, it will NOT be boring

I'm not a Gluck fan, so I can't comment on Armida.