Lorne acts in a stereotypically gay fashion but he describes Cordy as hot-o-rama suggesting he's actually Bi?
He does that a few times later on too, for example in "Waiting in the Wings." But I think he only does it to push Angel into his realization of his feelings for her. This is the same conversation where he drops hints about a big future for Wesley too (presumably referring to his actions in "Loyalty"/"Sleep Tight"), so it's clear that Lorne has his eye on the future already.
So yes, I believe Lorne is gay - a metaphor used effectively in the Pylea arc at the end of the season too.