I assume the OP is referring to use of wide gamut monitor with LR, so relevant.
If you are printing to a wide gamut inkjet printer (6 or more inks) than using a wide gamut display will be helpful. For web, screen, and printing to standard CMYK 4-ink printers it won't provide much better color accuracy than an sRGB gamut display. With LR4's Soft Proof feature you can get a very accurate onscreen rendering of what the final print output will look like using the target printer and paper profile.
Wide gamut displays will not render color properly with most web browsers and other non-color managed applications. Because of this I would also suggest using a dual display setup with one sRGB gamut standard display and a wide gamut display.
Also be aware that 10bit/color will provide better rendering of fine gradients on wide gamut displays, but LR currently only supports 8 bit/color display output. Only PS CS4-CS6 support 10bit color display output. You also need to be using a graphics adapter that supports 10/bit color, and one that is compatible with PS.
If you don't fully understand the differences between a wide gamut and standard gamut (sRGB) display I suggest doing some research. Also search this forum and the Web for reviews on displays you are considering. There have been numerous issues with calibrating certain model wide gamut displays.