He may do it elsewhere, but I believe here that David definitively states that he'll be 'going back to Russia'. Minsk is not in Russia, it's in Belarus. I could excuse this of the average man in the street, but not someone who spends most of his time there.

In explaining to Ross that being funny is Chandler's "thing," he elaborates by trying to point out what Ross' "thing" is, but intially cannot come up with what it is. But as Phoebe pointed out in The One After Vegas(6.1), getting divorced seems to be his "thing."

At the end of the episode, Chandler tells Monica that if her friend has any Oklahoma jokes, he should email him at www.hahanotsomuch.com. That's a url. Not an email address.

TRIVIA: Also, according to imdb, that url is for a real web page with various quotes from this episode, but when I tried it a few days ago, it simply directed me to a Warner Brothers page. When I tried it again just now, the browser wouldn't go anywhere at all.

After Ross and Rachel conclude an interview with one of their prospective nannies, they sit on the couch and exchange a few words, before they hear a knock on the door. They answer it, and it turns out to be the next prospective nanny. Aren't people buzzed into apartment buildings? And if Sandy snuck in or got into the building while someone else was leaving, wouldn't that make Ross and Rachel uncomfortable? (Of course, buzzing him in would require Ross and Rachel to hear his voice, which would preclude him from being surprised at his being male. Of course, they could've had Sandy show up with a female friend who drove him there, and say that she buzzed the buzzer herself...)