Not necessarily. If you were to quit and then go interview with a company that wasn't recruiting you, then yes, it'd look bad. But if you already mostly have a job lined up, as long as you stay there a good long while, it should be ok. Employers mostly want to know why you leave places so quickly. There's a big difference in being there short-term because you got fired or couldn't get along with people versus being there short-term because you are bettering yourself. Companies do want to know that their investment in you isn't going to leave them hanging 6 months from now though.

I'm rambling. Does this make any sense?