Definitely a kiss. Naruto may end up being clumsy or whiny in a confession...and Sakura would just stop him from being like that because she's not dense not to know what Naruto is going to say. Whew, that was long.
I think Naruto's the one who'll confess. Of course, in a comical way. Its not Naruto if its serious - it would be Sasuke. And the kiss would come from Sakura. Naruto's afraid of her punch(?), I guess.
Comical yet romantic - it can happen. That's NaruSaku chemistry.