Any chance this can wander into the subversion repository? I have a need for something exactly like this and the motivation to submit patches.
Also -- I grabbed the DMG and dropped the tmbundle/tmplugin into the right spots and:
/Volumes/Data/Users/bbum/Library/Application Support/TextMate/Bundles/ TerminalMate.tmbundle/Support/lib/terminal_mate.rb:7:in `initialize': No such file or directory - /Volumes/Data/Users/bbum/Library/ Application Support/TerminalMate/server.bin (Errno::ENOENT) from /Volumes/Data/Users/bbum/Library/Application Support/TextMate/ Bundles/TerminalMate.tmbundle/Support/lib/terminal_mate.rb:7:in `open' from /Volumes/Data/Users/bbum/Library/Application Support/TextMate/ Bundles/TerminalMate.tmbundle/Support/lib/terminal_mate.rb:7:in `initialize' from /tmp/temp_textmate.Ys206J:4:in `new' from /tmp/temp_textmate.Ys206J:4