On rare occasion we've seen the 10-Forward set redressed as definitely another room. "Frame of Mind" had it as a stage, for example.
Still, 10-Forward was supposed to be the best window on the ship, and arguably the only one that wasn't the Captain's quarters, that had an unobstructed, directly-forward view in the direction the ship was traveling - everywhere else on the ship has windows that looked more up or down than straight ahead. As such, they would certainly want to use it for prominent events on the ship, even if there are plenty of other lounges and such around.
Heck, it wouldn't surprise me that they would NORMALLY use the ship's chapel for weddings, but Miles or Keiko pulled some strings to get it bumped up because it's where they first met, or got drunk together, or whatever. The only other wedding on ship was the aborted Lwaxana nuptials, but her Ambassadorial status could have allowed her to be given away in a more prominent place.