I'm predicting an entire X-men reboot done more in the style of the Avengers movies. To date, the effects, casting and story for the X-men movies, while fine for the time, have been a big downgrade from the entire Avengers line-up.
> hype and fan expectations make Avengers 2 an inevitable let-down
I'm hoping it isn't. The second Captain America movie was a huge upgrade over the first IMHO, and I thought Thor 2 was at least as good as the first one. The Iron Man movies have been relatively good as well (sure they're going down a bit, but they're at least entertaining).
If the 80s were the action star decade, the 2010s are the Marvel movie decade.