I support this idea for purely selfish reasons. I write haskell in vim, and I'm constantly bothered by vim bugs that will likely never be fixed, and I don't dare try to fix them myself because vim source is such a jungle. I have several extensions for syntactic manipulation written in vimscript and python, and they mostly work but not entirely reliably because vim extension is clumsy. I use tags and they also have problems, but once again I'm not about to go in and redo vim's tag support. Etc. etc. Yi is tempting because it promises to be a place where I could fix these things for real, but I've been discouraged in the past by immaturity (can't even get it to build) and lack of documentation. So I think some concentrated attention to the build, documentation, general cleanliness, and performance would be a great idea. I'm not too fussed about a lack of concurrency since I think there are more fundamental problems, but if it would result in improvements to those fundamental problems, I'm all for it.