The candor about the trade-offs involved in picking one database vs. another is definitely appreciated and is a tone the community needs to take on the subject in general.
I agree PR and lots of BUZZ makes it really difficult to choose the right DB.
My latest obsession is Riak => Basho is VERY honest, and quick in helping you out and telling where and how Riak can help you, and most importantly what would NOT be a good fit for Riak. ( I am not working for them :)
/Anatoly