Oh my god. I was fully expecting there to be more networking, but to completely swing the axe on so many local radio stations is just awful. Given how popular some of the names are, I can't see this move going down well with listeners. I'll give it a chance, but for me, Greatest Hits Radio will never truly replace my local station.
This is no different to what Global has done with their stations, and based on Global's experience the reality is that while listeners might complain at first about loosing the local brands, in the long term they don't care. In fact they've gained listeners. From a TV point of view it's also very similar to what ITV have done, and it's done them no harm.
As long as listeners get a decent radio station that plays songs they like, they'll listen to it. Using national brands usually results in a better product, which is marketed better as they can run bigger ad campaigns (e.g. on regional/national TV), and usually results in a better sounding station even if it is less local. The use of split news and links often results in listeners not realising it's less local.
It's sad we'll lose established brands and that people will lose jobs, but it's a good business decision. The only bit I do find strange is that they've decided to roll out Greatest Hits to most the stations, whereas I would have thought the younger sounding Hits Radio would have been a better choice.