Roommates?

It shouldn't be any surprise to us that the girls have mentioned several times recently that they would like to share a room together.  I mean, they are only 21 months apart.  They spend the majority of their days together, they enjoy a lot of the same things, and they most recently have declared that they are "best friends!"

I'm not opposed to the idea of them being roommates; it sounds like a ton of fun.  Two beds (singles or a bunk bed), more toys in one room, more books & more babies to play with.  Someone to whisper and giggle with after lights have been turned out for the night.  Someone to wake up with in the early morning hours.  Someone to share funny stories with while you hide under the covers and pretend you're camping.

I am, however, wondering if they have any real idea on what they are asking for?
No personal space.  No space to call their own.  No place to go and close the door when they each get frustrated with each other... or even the rest of the world.  I don't mean to sound like Negative Nancy, but I'd hate for them (and us) to regret moving them into one room when in fact there was plenty of space for them to have their own bedrooms.

As we prepare to get rid of baby furniture for good and set our sights on a new house in Florida by next summer, this will most certainly be a big decision to consider for the girls. 
Roommates: To be or not to be?