I think this would mark the first time that MyNetworkTV stations not owned by Fox would be available on YTTV, and it fills a major gap in CW affiliate carriage on the service (many are already available on YouTube TV, with CBS and Sinclair being the largest affiliate groups prior to this deal that have carriage agreements for their CW affiliates).
In some markets, it means the majority of the major local stations - commercial and public television - will be available on YTTV’s lineup. For example, in Oklahoma City (my home market), it means KAUT will join sister station KFOR (NBC), Hearst’s KOCO (ABC), Griffin’s KWTV (CBS), Sinclair’s KOKH (Fox) and KOCB (CW), Tyler Media’s KTUZ (Telemundo) and KUOK (Univision, which was added this past Fall alongside the existing national Univision feed), and OETA (Oklahoma’s PBS member network). (This leaves KSBI, KWTV’s sister station and the local MyNetworkTV outlet, as the only notable commercial station missing from the lineup.)
And subscribers in New York, L.A. and Chicago will get access to WPIX, KTLA and WGN, respectively.
CORRECTION: Sinclair’s MNTV affiliates and CW affiliates owned by a handful of other groups including Tegna, Scripps, Sunbeam, Griffin, Bahakel and Graham are apparently also carried on YTTV.