with a resolution of 1920x1200 you will have black bars at the top and bottom of your screen. if you dont (and stretch the video to fit) you will notice distortion on 1080p content.
lcd technology does not have the contrast ratios that plasma technology does. however, lcd panels also typically last much longer hence the phase-out of plasma. this means that usually on a lcd "black" is more of a "dark grey" if using an even backlight or "panel color" if using zone backlighting found on some new lcd tvs. across the board the contrast is noticible between the two technologies.
as far as sharpness is concerned televisions may come with options you can change to "sharpen" an image. this alters the original content. perhaps you are comparing "original content" with this "altered-state content". if you want the image to be a little more crisp you can change settings on your computer to reflect this.
as stated by the others a glossy screen will make colors look more vibrant and in general make everything look nice, however, this reflectivity can make the screen hard to see in areas with direct lighting (sunlight for example). matte screens are much easier to see even in brightly lit areas. however, they don't have the "vivid" nature to the colors that glossy screens do.