When people had URLs in their IM status message, it was always a pain to access them in 10.5, since iChat did not allow selecting and copying them, or accessing them directly by clicking.

No more! When you see a URL status message in iChat in Leopard, it will show those iTunes Store-like arrows that open the link in your browser by clicking.

[robg adds: Interestingly, iChat will respond to file:/// links, though it won't seemingly open applications -- just the folder that contains those applications. This page, however, indicates that it's possible to run an AppleScript directly from a URL, which might have interesting implications for links (not just in iChat, of course).]