Omitting the predicate verb produces a sentence fragment, something you may wish to do occasionally for deliberate rhetorical effect. Like this. But too many sentences without verbs make your style seem telegraphic. Or silly. Like the copy in so many advertisements today. Use the verbless sentence sparingly, as you would other strong stylistic devices.
See also Purdue handout and excercise
Copyright 1996 Yale University. Revised on Monday, May 20, 1996