Ooooops? It's always messy politics when an actor is out to everyone around them but not to the wider general public. It's even messier when those two signals get a little crossed and Ian McKellan outs you during the Hobbit press tour. This particular case came out of an interview with German outlet Brash.de, in which he discusses being an out gay gentleman in 2001 (when the first Lord of the Rings came out) versus now (with The Hobbit: The Desolation Of Smaug). He also mentions the names of three other out gay men he's worked with: Luke Evans, Stephen Fry, and Lee Pace, as well as two of the Hobbit dwarves.
Stephen Fry and Luke Evans are of course both already out, as well as Hobbit dwarf Adam Brown. That leaves it open to guessing who the other gay dwarf is, if that's your kinda game.
Lee Pace, also, is less publicly out, though his sexuality has been assumed in that Zachary Quinto or Anderson Cooper way for years — namely, he hasn't said it to a reporter but he's been assumed to be dating dudes. This undoubtedly made a whole bunch of hetero girls sad today because his role as Ned the Piemaker in Pushing Daisies remains perfect husband material — don't worry ladies, I had that moment years ago — but it's not really about them right now, and I can't imagine this blowing up too much for Pace.
In fact, these days people (at least the ones who aren't raging bigots) are more likely to react negatively to someone they assume is gay living in the glass closet than towards the ones who try their darnedest to veil their sexual preference. We kind of can't imagine that Pace is raging at McKellan right now — if he's annoyed it's probably more of a Thranduil icy stare.
Pace was also the star of LGBT-themed movie Soldier's Girl, which isn't so much a clue as a movie you should watch if you want to see Lee Pace in the most realistic pair of fake breasts you've ever seen. It also might make you cry/rail against a don't-ask-don't-tell world, though, so it might be a wash.