Why can't a B2C press room be a blog? Why not indeed?
A blog would enable comments on press releases, links to important items like logos and fact sheets. It would provide RSS feeds for those so Interested to catch the latest. Enabling trackbacks and sharing, posting in multiple languages are all positives. Why aren't more companies doing it? Are they scared that their news will invite criticism? Is their news not good enough?
And how many companies who's media rooms are or contain a blog don't allow comments? If you don't have good news and don't want honest feedback that it's not good or press worthy, don't publish it in the first place. There's too much press spam, too much noise. Being a bit self-critical, or letting your readers provide feedback - and listening to them - has got to happen.
I don't see a drawback - let's do it.