I love the idea of having one big huge monitor, but for me speaker position is too important. I have my speakers either side of my monitor (how confusing is it that the word "monitor" both refers to speakers and screens) and I like to maintain a nice equilateral triangle with them and my head for the best stereo image. That means I can only go as big as my 23-inch Samsung before the speakers are too far apart.
So I have a second monitor instead (another 23-inch Samsung). This goes to the right of my right speaker and rotated inwards a little to face me. It makes for a little more head turning than I'd prefer, but you get used to it. And one thing I find better about two monitors instead of one large one is the organizational element. I like dividing tasks up between the two screens, for instance tracking on the main screen and mixing on the other screen. It feels tidier than having everything on one screen.