If you’re thinking that you can post here and there on infrequent occasion and your competitors are staying online and contributing frequently to their blogs and websites, you may want to take a look at the latest official Google announcements about their algorithm and ranking in search results. The proclivity to favor fresh content just got an even stronger boost with three of the seventeen updates touching directly or indirectly (the Panda announcement) on freshness as a topic of interest.
Real Estate SEO tip: If you have access to photos and descriptions of your listings ahead of everyone else and you have the OK to post that listing anywhere you like, you might want to put it on your own blog or website before posting it in any content aggregator sources like your MLS. Google algorithms recognizes posting times and will favor your website as the source of the listing content, giving it better ranking in search results. Aggregators may still place ahead of you but you will show up much higher as the source of the content instead of as another also ran.
Google likes fresh content even more than before. I believe this is more important than the old standard word count so frequently touted as good SEO, whether that magic number was 300, 500 or more words per post. Content may be king, but frequency gets noticed ahead of stale content and gets preferred treatment too.