I can give them Kirk acting like that at that age, but something about Uhura seemed odd. That whole "sex with barn animals" line doesn't sit too right with me.
What's wrong with it?
I thought Saldana's performance was great here, BTW. Her delivery is very Uhura-like, especially the dismissive "you have no idea what that means." And she communicates very clearly the fact that Uhura is enjoying herself - so clearly that you know her would-be "protector" must be fairly drunk himself not to pick up her clear signal to back off and leave her and the "farm boy" be.
Plus, there's a couple explanations:
1) It is an alternate timeline
2) Uhura is 4 years younger than on the series. It may not sound like much, but a lot of personal growth happens between your early 20 college days and your professional mid-20s and even more so when talking military officers.