You could also consider the MPL 2.0. It features file-based copyleft, meaning anyone who changes the files you're distributing has to redistribute their changes, but they can be used in a proprietary work without forcing the distribution of the source of any other file.

MIT is more widely known and understood, though.

yeah, strongly preferred.

here are two very handy articles about the differences between open source (and other) licenses

http://www.smashingmagazine.com/2010/03/24/a-short-guide-to-...

http://en.wikipedia.org/wiki/Comparison_of_free_and_open_sou...

Thanks for this - will change the licence to MIT.