That's 5pm PST, 8pm EST, 1am GMT, 2am CET Not long, but thought I'd give some slight warning for the Wikipediholics among us... ;)
I'll be upgrading MySQL to support InnoDB tables which have row-level locking which should help with the lag problem (actual conversion of the tables will be done later, after I've double-checked it on test.wikipedia.org).
Should only be down for a couple minutes.
-- brion vibber (brion @ pobox.com)