Hard to say, Mail.app doesn't break the addresses to begin with, so I can't tell if it worked. The problem is the worst for me when people are pulling messages off of places like GMANE and following broken links to my blog, and I don't think the brackets would make any difference once it's converted to text/html. Good tip to know, though, if it works.
Thanks, Brett
I read somewhere that mail clients (which I understood to mean "Microsoft mail clients") will work OK if you surround the URL with angle brackets. Therefore, here's a test, perhaps if the link isn't clickable to anyone reading this they could report back to the list with details of what mailer they're using?
In case it gets mangled by my mail client when I send it, I should probably indicate that too - I'm using Mail.app from Mac OS X 10.4.8.