I predict that in 2 to 3 years, there will be several accessible web frameworks in erlang, scala, and maybe even haskell. Yes, there are frameworks for them now, but they are not "accessible" to the masses yet. This will change and good programmers will have all the readability they need for quick web dev as well as the power and safety of more advanced language features.

As much as I like merb, I would like it _much_ better if it was in erlang or scala. lift, erlyweb, mochiweb, etc are still not at the ease of use level of the ruby frameworks. There will be a tipping point, I hope ;).