According to Weekly Shounen Jump, Dragon Ball Z TV series will be re-aired from April 5th to cerebrate the 20th anniversary of the series. The graphics will be upgraded to HD and the songs and the animations of OP and ED will be replaced with new ones. The cast is the same as the original and the voices and the sound effects will be newly recorded.
If they really are planning to cut most of the filler out of the show (making those horribly long fights reasonable), it'd be worth watching again. The ridiculously long fights killed my interest in the series beyond the Buu Saga and it almost killed my interest in the shonen genre. With that said, I won't go out of my way to see the series. If it airs domestically maybe I'll check it out.