I thought this was a really cute idea: an in-game date, sharing some of the best locations and activities around Azeroth with someone you love (or just happen to be courting). There are lots of great ideas in that thread -- I agree that the Twin Colossals is one of the more scenic (and out of the way) vistas to visit, but there are plenty more to go to: The Grim Guzzler, a floating island in Nagrand, the Darkmoon Faire, inside the bio-domes in Netherstorm. Personally, I think the best date would be a picnic on the deck of the ship in Deadmines -- sure, you'd have to fight off ninjas every once in a while, but what is a date without a little ninja fighting, right?
If you do head out on a date, make sure you bring some roses and a bottle of wine (depending on how well you expect the date to go). If you've really thought ahead, you can bring a Romantic Picnic Basket, or you can shell out for a regular Picnic Basket, but otherwise, it's probably just best to have a snack of Delicious Chocolate Cake (it's guaranteed to make your date Very Happy).
Like I said, cute. Spending the time together with friends is what the game is all about anyway, and there's nothing wrong with taking some time to experience the world and hang out with each other. And if that's a little too boring for your tastes, maybe you can have your date tag along with you to some 2v2 Arena matches afterwards. Nothing gets the romance going like a little bloodshed.