It's noticeably more humorous. Due to one reason: BVS. The last trailer was a GOTG rip off in feeling, and though there was humor it was mainly selling itself on how it was irreverent and quirky to pull in that GOTG crowd. This was before BVS. Now they're not even hiding the fact they want this to be more humorous and fun to the masses, especially in the wake of BVS's failure. This movie's marketing keeps getting dialed into more wacky and fun fare than the dark and fitting Comic Con trailer.
This doesn't look like GotG at all





