FsLex and FsYacc are not language (orientented) featuers but tools to implement you lexers and parsers (the kind you learn about in all those "compiler building" CS coursers or in the dragonbook).

So it's not build into the language but it translates some other language (for describing the parser or lexer) into F#.

Quotations are nice but it's kind of hard to find any good applications for that and it's more or less a framework feature that's only adapted to F# - just like the dynamics thing and C# - or Linq or whatever.

Computatinal expressions do really shine and the most usefull (async is REALLY usefull) is allready there - it's more or less the basic monad stuff (but you might find yourself struggeling to implement the more advanced monad-operations).

I think it might need some polishing (in the end a computational expression will give you a codeblock looking like .... imperative programming ....) but it's worth a look.

To be completely honest: I don't know Boo at all and it's a long time since I wrote any Lisp code (but I think I can remeber the macro system) and I think you just can't compare this.

So what advantages / disadvanteges are there?

Well a bit + for F# is the fact that F# is a CLR - languague so you live in a VERY rich environment and you can basically target everthing there is (most OS, most Hardware).

Disadvanteges: none I see that would matter in a real life scenario.