Should I paint my vaulted ceiling the same as walls in my bedroom?

Well it depends. Do you want them to blend in? If so paint the same as the walls. If you want them to stand out and highlight them, then paint a shade or two lighter - or darker, or a complimentary color.

If you do, it may lower the look of the vault. A lighter color will heighten the look of the vault. It really depends upon the look you are trying to achieve.

I prefer white on a ceiling and color on the walls (unless they are white, too), but you could try painting a large swatch on some pasteboard and seeing how it looks compared to your wall color.

If you're thinking of a darker color, be careful not to create a 'cave' effect.

Why not a similar hue to the walls, either a little lighter or a little darker, with a gold, bronze, copper or silver trim? Richness, YES! You could even add some discreet lighting tucked around the edges using those light tubes that come in lengths. Or, if you like looking at the heavens, you could paint it a cool blue with "clouds". Or a night sky, dark blue with toothbrush splattered "stars". Don't be afraid, paint can be covered. Good luck.

We painted our ceilings with half the tint used on the walls. Worked out great!

I have vaulted ceilings and painted mine the same shade as the walls. I hate the looks of a white ceiling. It looks like a huge diaper or tissue that is stuck on the ceiling. For me it was a wonderful change. But to be fair my wall colors are a light blue (in the bedroom). I choose that color to contrast with the furniture which is a matched set of dark wood. Come to think of it every room in our house except 2 are all matching walls and ceilings. I like to add pops of color with accessories.