Glass tops definitely easier to clean than non-sealed burners, but I always end up with charred rings over the burners that have been polished into the glass and will never come out.

With sealed gas burners I just pour some boiling water on the cooktop, wait for it to cool, mop it up with a towel, and scrub the nasty stuff off with a scrubber.

Inductions are crazy easy to clean, though.