I like more of the lean muscle look like soccer players or swimmers have. Stick thin guys like the first pic look sic and I think big buff guys intimidate me to much or they usually don't have a lifestyle that I'm down with.
I'm starting to love my boyfriend's build more and more. He's way too muscly to be considered skinny and has pretty nice big arms, but he's not freakishly buff. He thinks his belly is too soft and wants his 6 pack back, but I don't think you need a six pack to have sexy abs, as long as you don't have prominent gut.
In general I like strong arms, broad shoulders and strong cores. Flat stomachs are pretty damn sexy. Also, curved waists. emotion_dowant
As for the pics:
I don't really find the first picture attractive, though I do like his stomach and it looks like he's got pretty toned arms. I think I'm off put by the whole scene/emo look. It just doesn't do it for me here.
I'd probably piss the second guy off by playing with and giggling at his pecs. Too ridiculous.
Other than those, me gusta.