I hate it when people have an idea similar to mine and then blog about it first, so that I don't get the chance to claim it.
Anyway, that person is Seth Godin, so I'm not mad.
Real Estate agents (and anyone else with a local business) should read his post, Time to start a newspaper.
Of course, this is what your newsletter can become. Indeed, I have several members who have gone some of the way towards implementing what Seth is suggesting, with what's on guides and ads from other local businesses.
By making your newsletter into a real community resources in (let's face it) a time when many local newspapers are withering and leaving a gap in the market, you will become *the* trusted local expert, the go-to person - and you will own a strong relationship with a section of your community.