I was strolling through Central Park on a freezing winter's day and found myself hankering for a cortado. I was lead straight to Joe's after reading some other reviews, and I was not disappointed. The coffee here is good, and possibly the best I've found this high uptown. However, it's not great! My milk was over done; it looked (and tasted) like it had sat on the bench for 5mins prior to drinking. The bean was tasty, sour with a long finish. But it could do with a longer roast, it felt unfinished.
The cafe is popular and the seats are few (Welcome to the NYC coffee scene!) but if you can snag one it's good inside. The service was lovely and friendly, and they have a good knowledge of locals who frequent it. Which is better than can be said for other US stores.
Overall, I think it's worth the trip if you're in the area.