I am hoping to generate a few opinions on this subject. I know many agents use both VFlyer and Postlets. Both are good services and allow you to post listings to many national portals.
However, in doing this, I can't help but think that you are compromising your own website. Both of these are services about promoting themselves - the listings show up on the portals as either Postlets or Vflyer in the URL. You do have a clickable feature to your site in the body of the flyer, but its still not the emphasis.
On many of these portals you can directly load your listings and customize how you want the information to look. Many allow you to direcly add HTML tags, and I would believe this will only increase as time goes on. It is clearly more work to do this....but aren't the results better for the exposure of our own websites?
ListHub is also available - but this does not in ANY WAY provide support to indivdual agent websites - it all about the agency only.
At the end of the day I don't really think potential buyers are searching all these portals for homes - oodle, doogle, boodle, woodle, whatever! They are sticking with the big guns - or more importantly searching Google, Yahoo and MAYBE MSN for local real estate website (and listings). If you really do any searching online for homes, and test these different sites, they really are not that good and the so called neighborhood information they provide is pretty vanilla - and all the same. It is my believe as local agents we can create a better online experience for buyers. Can anyone really identify any leads coming from any of these secondary portals - my guess is that it is pretty limited.
Just image what would would happen if we stopped suporting all these real estate portals.