The San Francisco Association of Realtors MLS has quietly introduced new "new lease property types for single family, apartment, and commercial listings. The new lease property types will also include a variety of listing price styles such as per month, per week, per day, as well as per square footage."
Properties for lease, especially residential properties, are common in the MLS that serves north bay communities but this is the first time I know of that the SFMLS has allowed them.
For commercial leases, this begins to infringe on what has been until now almost the exclusive territory of LoopNet. While both LoopNet and the SFMLS have carried listings of commercial properties for sale, LoopNet has been the only widely available database of commercial properties for lease.
On the residential side, since landlords already have Craigslist to post their rental/lease residential properties and many landlords won't pay real estate agents a commission for finding a tenant, it will be interesting to watch whether these new categories of listings have any real effect on how the residential rental market works.