John Englehart (regexkitlite developer) has posted to cocoa-dev saying that apps are being rejected for using it. http://lists.apple.com/archives/Cocoa-dev/2010/Jun/msg00564.html
(Apologies for this purporting to be an "answer", it would be a reply to Kendall Helmstetter Gelner if only I had 49 more reputation points).
