It also doesn't hurt that the villain of the mini-series is THANOS, who himself is set to be the next big bad villain in the next Avengers movie. There will be a Guardians of the Galaxy movie to tie that team into Avengers 3. The Guardians are also very closely associated with Thanos in the comic. In fact he is their number one villain. They are on the front lines of the battle whenever Thanos starts rockin' and rollin'.
Of course the third thing that makes my story great it that is all revolves about the struggle to acquire the INFINITY GAUNTLET. This glove holds the six soul gems. Each gem itself is immensely powerful. Once they are united, the person wearing the Gauntlet has near Godlike powers.
If a great story wasn't enough the Pet Avengers themselves are a great bunch of characters. I love the Speedball the cat who acts just like a mega-hyper cat would. Who ever thought it would be the dim witted dog of Aunt May, Miss Lion, that would steal the show and the biggest share of all future merchandising profits? Even Spider-Man's dog has a place in the grand adventure - which is how it's meant to be.