I found this thread that gives a good overview:
http://www.realestatewebmasters.com/...ad.php?t=10236. I now realize that I'm currently using a "A vendor-provided and hosted IDX-only plug-in solution" and that seems to be the option I want to stick with. However, now I'm interested in what other vendors provide this type of solution and what sort of variance can there be and how good the IDX Broker product is in comparison?