If you're buying in the US, the D90 is the best for the money. The price gap is small between these two. The D5000 may give that cool swivel screen but IMO, that's one more thing that could break. The both most likely will give the same look to their images as the use the same sensor. The D90 will give you more controls on the outside while the D5000 has more things buried in menus. This will be important as you shoot and need to make changes quickly, otherwise you can miss shots.
Now if you're on such a tight budget that the extra 150 to 200 dollars just isn't a reality for you then the D5000 would be your choice if you want the same quality and if video is important to you. Otherwise, I'd say between these two choices you asked about, the D90 is a better option.