I believe there are currently three satellite based IPTV services:
Intelsat has Intelsat IPTV:
http://www.intelsat.com/_files/services/media/IPTV-factsheet.pdf
SES Americom has IP Prime:
http://www.ip-prime.tv/ipprime/index.php
Echostar has VIP-TV:
EchoStar ViP-TV™
Intelsat uses Galaxy 23 and Galaxy 13 Cband.
SES Americom uses AMC 9 Cband.
Echostar uses AMC 16 Ku Band.
Some IPTV services are internet based. But the service that NPS is hoping to implement is satellite based. The services are mainly for telecom and small cable companies who would receive the satellite signals and send the channels to customers over their own lines in IPTV format. NPS wants to set up a system where Cband owners can receive the satellite signals directly through a special set top box. I believe NPS will be using Intelsat for their IPTV.