Ah, Ultimate Spider-Man Annual. How I've missed you. In case you haven't heard, coming October, Ultimate Spider-Man Annual #3 will hit the comic shops. The issue will deal with the birds and the bees. You know, the horizontal polka. The wild monkey dance. "Houston, we have lift off!" That sorta thing. Still don't know what I'm talking about? Sex. There, I said it. USMA #3 will deal with the issue of Peter and MJ deciding on if they should take their relationship to the next level.
Now as surprised as I was to initially hear about this story, teenage sex is still a hot button to this day. It isn't going to go away anytime soon and its only natural that Ultimate Spidey tackles such a subject.
So will Peter and MJ do it? No. Way. Why? Short answer: This will bring so much unwanted crap down on Marvel. More in depth answer by Morbius from the Crawl Space Message boards:
"I would love to see this happen because it is realism, and it's time in their relationship. It's a real piece of the character story that's just not dealt with often in other books. It would add a whole new layer of humanity and relatability to them as characters. But the unfortunate fact is, it's not going to happen. If they had young, underage Peter Parker have sex and not immediately denounce it as a terrible mistake (which would ring very false) the media would string them up from the nearest flag pole then draw an quarter them for "advocating teen sex," because we all know that's what they would call it. The minute it happened, a crap load of old, bald white guys and mom's unions and whatnot who have never read the book in their life would be on the news talking about how important this book is and how it's betrayed our kids, telling them it's ok to be immoral and have satanic sexual relations outside of wedlock. Just like when a bunch of people who have never read the comic in their lives got on the news and said killing Captain America at a time of war is irresponsible and sends the wrong message to the troops. I'm quite sure the reason it took him a year to get this greenlit was simply having teenagers seriously talk about having sex. I will be utterly bowled over if they actually go for it."
It should make for quite a story, but Joe Q sees Peter Parker as a role model for the kiddies. So Peter having sex in Ultimate Spidey is off the table.