Avengers: The Children’s Crusade, Allan Heinberg, Jim Cheung, Olivier Coipel, Alan Davis
Children’s Crusade is pretty awesome. It’s not exactly a pure Young Avengers comic — it’s definitely a crossover comic — but it does feature quite a lot of Billy being awesome, supported by the other Young Avengers, and a fair bit of Teddy being awesome. It also features their first (I think) on-page kiss, and is generally more blatant about their relationship than the other comics so far. There’s some awesome dialogue, and some lovely funny geeky bits about Billy and Teddy.
It also pulls in the X-Men, the Avengers, backlash from House of M, and features quite a few characters we know and love (or hate).
It’s also not without consequences, as even the Young Avengers lose people from their line-up.
On the other hand, I can see some other people’s problems with it: it seems to go back on some previous Marvel events and erase their consequences, and it really is one gigantic squabble between various superhero groups, with the teenage Young Avengers coming out as maybe the most mature.