In build 1505 'Edit in TextMate' fails for me, whether I select it from the menu of an enabled app (Mail, Safari, OmniWeb) or depress its shortcut key (Cmd-Crtl E). Tried it with several apps and with TextMate already running, open in the background.
Leopard 10.5.7.
Same thing here: same configuration and same problem…
Edo