IPTV, as a competitive alternative to cable or satellite TV, is most effectively delivered over a closed, local, isolated controlled network. Only "last mile" wire providers can provide that closed system, and Cable already delivers TV, so doesn't need IPTV, so that leaves telcos. Most IPTV systems are a system closed to the local telco, and hardware.
Companies like GekTV compete by providing a conduit for niche programming that traditional TV providers do not or cannot deliver. They are technically, IMO, Internet TV, since they deliver TV over the general internet, not a closed system like telco based IPTV service.
As for the world of Internet TV services, they are generally not competitive with traditional providers, and each provider typically uses their own box or PC software package, if not streamed from the web. Also, some content providers may not sell to or otherwise block their content from Canadians.