I went ahead and submitted a patch that implements this. Hopefully it will be accepted and merged into 0.10.

I am looking for some suggestions for alternate flavor text on criticals. These are the messages like "you open the kobold like a pillowcase", "you spit the goblin like a pig", and "you dice the ogre like an onion". I think they're great, but some more variety would be ...

I made some mac binaries that are ready for testing: http://charm.cs.illinois.edu/~abecker/crawl/