Babylon 5 is probably the best, or at the very least one of the best, Sci-Fi TV shows of all times.
The B5 universe is extensive, and the plot is probably one of the best thought of and written works on TV. It has created a vast, loyal fan base for the show specifically and for J. Michael Straczynski in general.
The DVD release has made over 500 million dollars in revenue so far, but many fans will gladly pay twice for an HD Blu Ray release, if it is done correctly.
Furthermore, a fresh, HD Blu Ray release might raise interest in the Sci-Fi community and open new opportunities for TV, theatre of home video releases.

What else can be done?
Go to Amazon's Babylon 5 Blu Ray page: http://www.amazon.com/Babylon-5-Blu-ray-Jerry-Doyle/dp/B001CUFI7M/ref=wl_it_dp_o_npd?ie=UTF8&coliid=I2MOLZC4SA6BFW&colid=2UJMQAE9NZJO6
Sign up to be notified when this item is available and add it to you wish list. This will put preasure on Warner Bros. and show them how much people want this release.