Web 2.0 and mashups provide opportunities for exciting new applications. However, the security model of the underlying browser technology is quite inadequate to deal withthe new trust and security issues.
Dion Hinchcliffe wrote an excellent summary of 17 products in the mashup tools market (July 2007). He tries to answer the question: "What's typically missing from today's mashup platforms to make them both useful and desirable in the enterprise?"