So apparently a lot of middle-aged and older people specifically look for homes that have master bedrooms on the main floor. On the other hand, there are a lot of younger people who like the idea of the master bedroom on the second floor. Either way, I don't think it's a big deal, unless you specifically want the bedroom on the second floor.
We're younger and like the master on the second floor because during the spring/fall when it is more temperate, we like the idea of being able to open the windows while we're asleep. On the first floor, it's easier for somebody to climb in the window. Not that it's impossible on the second floor, just harder.
Just another thought.....especially as any kids grow up, if you have the bedrooms on the same floor, you probably don't want to share a wall with your kids. Makes it easier to enjoy adult activities without traumatizing your kids.