Should I fix my plasma?

My 2005 vintage philips plasma 50" has a wide splattering of black dots all over the screen. These sometimes go away after 30 minutes but sometimes they stick around for a couple of hours after I turn on the tv. When the spots are gone the picture is gorgeous. Would it be better to just get a new tv or try to have this one fixed? I wouldn't mind getting a 1080p upgrade and maybe even going bigger.