I personally like the contrast of brick/white or off white. Without seeing the rest of your stuff -- its hard to suggest another color.

We had a similar room in our home--exposed brick on one wall and plaster on 3 other walls. We went back and forth on color options and ended up choosing a burnt orange/saffron/terracota (you get the picture!) color that worked really well without making it feel like it was Halloween all year long.

I agree with pipertm. If you want a warm feeling with your room try to choose colors that are in your brick. Or you could whitewash the brick, if you wanted to move away from the orange/red hues and try something totally different.

we did red from Behr being that it will be a family room, http://www.flickr.com/photos/dylljumeaux/1581866857/in/set-72157600128652875/.

And yellow (sherwin william's madeline) in the baby's room:
http://www.flickr.com/photos/dylljumeaux/472651223/in/set-72157600128652875/

And Blue in our own bedroom:
http://www.flickr.com/photos/dylljumeaux/472651209/in/set-72157600128652875/

My first thought is that a nice pale butter yellow color would be pretty and cozy. But like robyn said, it depends what else you have in your bedroom.

paint the brick white. paint the mirror frame ivory. move the TV! is that's indeed a working hearth, that should be the focal point in the room. I loathe LCDs/Plasma TVs above or adjacent to fireplaces. it sucks the energy and visual warmth/comfort of the fire.

I don't have a paint color suggestion, but I like the idea of thinking of the brick wall as a built-in accent wall. It is so pretty.

I used a pale yellow next to a similar brick wall and painted an adjacent wall a warm gray that matches the mortar color. I'm quite happy with both : http://www.apartmenttherapy.com/ny/fall-colors-2006-east/32-bryans-demarcation-zones-013680

Fallow and Ball's London Stone is a nice variation on my personal favorite color, paper bag brown. You can also have it mixed at 1/2 tone, if you want something lighter. I used Aura, and Par's Paints in LA did a great job of matching the F & B color.

F & B has a number of good colors that tone nicely with brick walls.

grass-cloth wallpaper...

I like the idea of a grassy greeny hue. Kind of a tree idea, right? Brown bricks, green walls? :) I just don't really like oranges, yellows, or reds so I would naturally lean towards something else. Plus I think it's a little more unusual to see something other than those color families paired with brick!

I really like the deep red of that dresser/table in the corner, but maybe that would be a bit much on bedroom walls. If this was your living room, I'd say go for it! For a more soothing room, a butter color with lower light would be nice. The "paper bag" suggestion sounds like it would be very cozy.

I'd paint the brick white. with lots and lots of paint, so it doesn't look crumbly at all. I love that look.-- so clean and textured at the same time. Unfinished brick looks very rustic to me-- not a look I appreciate outside of a woodsy cottage. Was it the Darryl Hannah character in Wall Street who derided the Upper West Side as "home of the exposed brick wall and the hanging plant"? Ouch.

Not that I take my design tips from Gordon Gekko. But I do think you might consider what it would look like if you painted the brick to match the plaster, and not vice versa.

If you really want a seamless look, paint the adjoining walls a color that matches as closely as possible the mortar color. Or that color but anywhere darker on the same chip.

Btw, I'm not sure the question was "Should I paint the brick?" but rather "What color to paint the surrounding wall?"

Don't paint the brick. Exposed brick is so lovely and it wants to stay natural. That is the intention and nature of it as a material from the earth. Un-natural and man-made materials want to be changed and played with. Brick likes to be clay and have the ability breathe.
Find the 3 most common colors that are present in the brick, and then use those to pick a contrasting color. The pictures that *filles* provided links to are good examples. Something in a lighter shade of a complimentary color (like blue or green) could be very lovely. And I would either pick one color to paint only adjacent to the brick, and paint the other 3 walls something else, or do all 3 walls that portion the same color.
I have exposed brick walls in my apartment (one reason we chose it), and we could never agree on an orangey color for any of the walls. The walls are either the original white rental paint, chocolate or a misty pale blue.

Brick is not precious, paint it.

I lived with dark brick walls in my last place for years not knowing why I hated the space. Then I painted the brick white, and joy, joy, joy filled my home. I still had all the texture, but I no longer had that dark life sucking brick overwhelming the space.

It was also nice to no longer have brick dust everywhere.

I think brick looks great with pretty much any color, but then we don't have much here (grass, greener, etc...).
All the examples people linked to looked great with brick, so I think it's a matter of your style.

the suggestion to consider painting the brick was not intended to disrespect to the question or indicate that I can't read-- it was just an idea to take or leave about another way to soften the harsh contrast between the two surfaces. brick is beautiful, it's true, in many different ways.

I think the owner's comment "lovely brick" indicates she is commited to keeping it.

But to minimize the visual jump to the brick, stick to a warm color roughly the same value as the brick.

The other thing to "warm" the room is as much about lighting as it is paint.

I'd go with a rich putty gray similar to the mortar color. Also, adding a mantel shelf of some kind would help anchor the weighty mirror.

Wow, thanks for all of your great suggestions! And don't worry, that ugly big TV is on it's way out. Because we're renting, we actually can't paint the brick (and I don't think I'd want to anyway). But I really like the suggestion of taking the mortar color, maybe a blue/gray. I think elegant is more our style than pop. And no, unfortunately, that is NOT a working fireplace...though I AM SOOOO tempted to put in one of these www.ecogreenfire.com/renovator-range.php .

I think that instead of a blue, I'd do a warm grey, which is probably what that mortar is.