I can not figure out, why are there two quite overlapping specifications. While WS Metadata spec (JSR-118) defines WSDL-Java mapping (annotations basically), JAX-WS (JSR-224) also defines set of annotations for WSDL-JAva mapping. So why do they (JCP) created two spec instead of extending one of them?
I presume you meant JSR-181 not JSR-118. My guess would be that BEA wanted something NOW to put into Weblogic to compete with the equivalent feature in .NET. (see, developing Web services in WebLogic is just "as easy"). Also the annotations specified in JAX-WS 2.0 (JSR-224) seem to provide you with more control. However JSR-224 does explicitly support/include JSR-181 (JSR-224: 7.10 Annotations Defined by JSR-181).
What gets me is how some of these annotations end up obfuscating the code (see JSR 181 Annotations) - nothing like a @WebParam annotation inside of your parameter list to break your flow.