If you put "painted brick walls" in the Houzz search box and click on Ideabooks, you'll get awesome results. You can also do a search on "painted fireplace", clicking on Ideabooks or Photos. Houzz is loaded with ideas. I had this quandry with my own large brick fireplace wall, but I just didn't want to paint the bricks. So I had sheet rock installed over the brick, leaving just enough area around the hearth so that the bricks were now an accent, not the whole wall. Came out great, much more updated.

Same here. We freshened up the color scheme in our 1920s bungalow, but the old red brick fireplace just seemed to suck the life out of the room. After years of cajoling, my wife let me paint it the trim color (BM Linen White), and now it's beautiful.
Go for it!

There you go. I think it depends on the style of the home. Painted brick looks great in a bungalow.