After a long period of not integrating patches, I've released the newest version of mytop.
mytop is a console-based (non-gui) tool for monitoring the threads and overall performance of MySQL 3.22.x, 3.23.x, and 4.x servers. It runs on most Unix systems (including Mac OS X) which have Perl, DBI, and Term::ReadKey installed. And with Term::ANSIColor installed you even get color. If you install Time::HiRes, you'll get good real-time queries/second stats.
Give it a whirl and let me know of bugs or feature requests. To discuss, hop on the mailing list.