I echo this. If you can take it sooner. Do it. Make it happen. Otherwise, consider applying the next cycle.
If you have a 'knock-em-dead' application and you don't care about later interviews, go for it, you might be just fine.
If you do apply this cycle, and take the MCAT late, make sure you submit your complete primary (sans MCAT...there's a place for 'expected MCAT') waaaaay before August (like beginning of June) as soon as the schools get your MCAT scores they'll send you a secondary (or some schools will send you theirs before then). Be sure to return these secondaries before the MCAT scores arrive, or soon thereafter as you're already behind on time. Remember, by the time they look at your application they might already be interviewing the first batch of applicants.