From people who interview him and ask about things like a potential Angel TV movie or anything involving the Buffy-verse? It's the same way that William Finchtner hates Invasion and pretty much dismissed any mention of a fan campaign meant to save the show. Serious actors are serious business. SF pales in comparison to TV procedurals and whatever the hell Prison Break is.
I've never understood the fascination with Boreanaz. Between seasons 1 and 2 of Buffy, he aged 10 years and gained 50 pounds (and then kept going). If we're talking season 1 of Buffy, then yes, he's smoking hot with a beautiful face. Later than that, no, not appealing IMO.
That's ironic because his role on Invasion should have been catnip for any actor (maybe he recognized that the writing was meh early on but they got much better toward the season's end). More interesting by far than what they've got him doing on dimbulb Prison Break.
It's funny, because when Ausiello interviewed him at a Fox event, he had a "Save Invasion" t-shirt on to... suck up, I guess. And Finchtner just told him to fuck off, in so many words. The old TV Guide crew has similar stories of Boreanaz's reaction to anything related to Angel. Strangely, I think it was at the same Fox PR event. I guess I understand why someone would get tired for the same question... it'd be like asking some music act when the band was going to do a reunion tour over and over again, but he could be a little more magnanimous about it.