I'm a bit torn about how to feel about this, having dedicated a lot of time lately telling people to use Merb and why I think that it's superior to Rails.
On the one hand, it'll be good for Merb usage, as people using Rails 3 in big projects will now essentially be using what Merb 2 would have been.
On the other hand, I'm concerned with the technical hurdles that the core teams are going to have to deal with in order to make this actually work. There's a lot of old crufty code in Rails that needs to go, although I'm not sure what removing it would do as far as backwards compatibility is concerned.
I've been talking in IRC all morning about this, and I'm sure I'll have more thoughts as things move forward, but for now I'll just post some of my favorite quotes from today's IRC session here:
<devjj> Modular meaning, what, not included by default, gem install rails-bad-ideas <gruntruk> this is like biggy n' pac hugging each other <bitbckt> so, I presume the quality of conversation in #merb will disintegrate into #rubyonrails :-/
Certainly should be an exciting couple of months as this merge happens...
(Credit goes to an IM from my friend Will for the title of this post.)