Jack missed out the snake episode somehow (presumably because his mun was too busy) so he's comparing this less to that and more to his own body-swapping experiences with Reid and with Spike himself.
And his earlier very interesting encounter with a very nude Kirk on the beach.
"Mmm, it's weird, you still look like you, just... female. Different from having actually switched with someone else, I guess. And you're incredibly pretty as a guy anyway, so I guess it's not such a huge step for you as for some!" He grins. "Still got the killer cheekbones!" Even if they're a little rounder with this face.