There's no original content in this post, but here's what people are saying about WCF and ASMX interoperability in the Microsoft forums and other blogs over the last month or so:
WCF method returning a strongly typed collection to a .NET 2.0 client
Trouble getting a WCF return a collection to a .NET 2.0 client
Issues with generating .net 2.0 client for consuming a WCF service
Making an asynchronous call from a .Net 2.0 client(asmx) to a WCF method
netTcpBinding and Java Web Services
WCF and Java WS client
WCF bug in message deserialization?
Interop problem: WCF service & Java client
.NET/Java double-dimensional (jagged) array interop
Custom Binding requires a Timestamp
Accessing : <?xml version="1.0" encoding="UTF-8"?>
Why your NetCF apps fail to call some web services
How to Create a SAML token parsing the SOAP / RSTR Response
WS Security interoperability between Java and .NET web services(Urgent)
Interop Briefs: Begin at the Beginning...
New WSIT Plug-in coming
Sun understands WS-* very well!!!
SOA and WCF
Can Sun do WS-*?
calling a webservice from classic asp - what are the limitations?
SOAP Services and XML