Re-reading this, I realized that, while I was at it, I might as well just post the Matlab bundle for Textmate. So here it is.
Disclaimer : I am not the author of this, I just checked it out of the textmate svn server. If you know who is the author, please let me know.
Update (2006-12-26): I have fixed the link and upgraded to the last version of the bundle. Apparently there’s no maintainer.
Update (2008-04-08): The most up-to-date Matlab bundle for Textmate should be here.