It is now a double tap with three fingers on trackpad, but does not continuously update like the old command.I used to use the dictionary a lot where you could press cmd + crtl + shift + d and hover your mouse above some text. Has this gone now in Lion or can it be turned on somewhere?
Looks like you can just do a right click/look up on each word and it brings up dictionary, thesaurus, Apple and Wikipedia.I can't activate it with my magic mouse. My taps either activate the zoom function or mission control. Sorry.