"In this way, "Humpday" is less about the blurring boundaries of male friendship than an examination of a classic alpha-male power struggle. It's impossible to believe either man actually wants to have sex with the other.
Instead, they appear to be more interested in figuring out how far they can push things in order for the other guy to back down first. Setting this struggle within the world of the liberal artistic community gives it an extra freshness, if not the edgy transgressive quality some critics have assigned the picture: After all, Michael Mann has been examining alphas going toe to toe for years."
Times gives it 2 & 1/2 stars, not sure what that means in their context (do they go up to 3 or 4 stars?), but the review is positive, I'd say. Check it out here.