Lambda the Ultimate

Given the recent discussion on topics like Nemerle and C# 3.0, Apple: procedural -> OO -> AOP -> advanced procedural, and other AOP type design concerns, it seems to me that a structurally typed, functional, multi-method (maybe plus predicate dispatch) programming language would allow for FP, OOP, and AOP development without requiring language-external solutions or hacks. Nice and CLOS support multi-method, but not really any other languages. Is there a reason that there is no discussion of multi-method programming? Is it simply too complex to reason about? Is it too slow? Or is there something else that I have missed? Thanks.