They've fixed that 'oversight' in the MyCE beta style (now dubbed a "skin"). There's a little "Hello Guest..." box near the upper right of the homepage, which if you look carefully (and if you're slightly intuitive) includes a login link. That could be improved to make the login link more obvious, such as by making it a different color. However it fits in with the generally drab and non-functional appearance of the MyCE beta style, so I guess somebody up there is happy.
Logging in thereby went OK except it kept the terrible MyCE beta skin. However there's an member option... Edit Forum Options, Forum Skin (at the bottom of the long list) where you can select something other than the default MyCE beta skin (such as google...). Then it remembers your skin preference the next time you login.
Normally I've been able to stay logged in by keeping the cookie, but not yesterday, when I guess they tossed their cookies.