From same publication re: ADSB
If you aren’t happy about getting a transponder, you are going to hate getting ADS-B! The minimum equipment required for general aviation aircraft is a Universal Access Transceiver, currently available only from Garmin (the GDL 90). It’s a 4" x 8" x 12" box that weighs 6 pounds, requires 1.5 amps, and costs ~$7000 (Oct. 2007 price) uninstalled! If you want a display so you can see surrounding traffic, get weather updates, etc., you’ll need something between the $1000 PDA/software solution and a Multi-function Display (MFD) like the $7000 Garmin GMX 200.
ADS-B has a lot of promise, and eventually the equipment will be smaller, cheaper, lighter and use less power, but it’s unlikely to be a solution for glider pilots for many years. Fortunately, transponders will be part of the ATC system for many years (12-15 years for airplanes, probably longer for gliders), providing most of the safety benefits that ADS-B can provide.