I have a strong interest in web service frameworks. In general, I am of the opinion that the WSF is where MS & IBM wil have their next major battle. So, they HAVE to agree on a certain sub-set of functionality (those concerns which must be remedied at the protcol level), but beyond protocols, the field is open and the battle will begin shortly.
Right now, Sun has a set of api's that they call J2EE (JMS, JNDI, etc.) They expose each of these api's in a "java only" format. Microsoft has a similar set of api's on the .Net side. In my opinion, we will quickly be moving to the exposure of technical architectural elements as web services (web services front ending LDAP, web services front ending databases, etc.) We will also see web services frameworks for horizontal domains (accounting, crm, etc.) and vertical domains (insurance, travel, etc.) Each of these horizontal and vertical frameworks will have to pick a substrate layer to work with.
One of the more interesting web service frameworks is GAIA from TME. I like the fact that TME knocked out a quick impl of a soap engine (glue) and are quickly moving into the substrate. They are looking at the world from a set of concerns (scalability, availability, deployability) and identifying remedies (balancing, resilience through redundancy, etc.) Many of the problems that GAIA takes on are concerns that either were done in proprietary hardware (cisco stuff) or concerns that were handled in a monolithic app server (availability through clustering). I am a huge fan of re-addressing these remedies via a consistent web services approach. Using a balancing web service, or a caching web service inside of an orchestration makes a lot of sense.
Other frameworks have popped up, but at a higher level. One such framework is the sForce web services api from salesforce.com. The sForce api is early. It provides some real basic services (insert, update, delete, change password, logon, etc.) You can really view this framework as a "data service" framework - and from this perspective, it does the job. Their choice to use a significant amount of abstract data types (records & maps) facilitates versioning and adding new data fields easily, but has the trade-off of potentially introducing typing errors at run-time. Sidenote: This framework looks a lot like the old MS My Services (aka Hailstorm).
Web service frameworks are now emerging. It shouldn't be long before MS & IBM throw one (or several) out. It will be nice to move beyond protocol crap (ws-boring, service substrate) and into value-add.