I would think the fact that the '[decorators]' syntax can be implemented in pure Python (no changes to the interpreter) for existing Python versions would give more weight to it.
Can it? I must've missed that. It sure sounds like an incredible hack -- how to you prevent the default behavior that the list of decorators is thrown away by the interpreter?
That is, if someone wants to implement a decorator that's forwards and backwards-compatible, that's possible with the list syntax, but not the @ syntax.
.. but that also means you can still make the [decorators] syntax work in 2.4, if you want compatibility or don't like @syntax.
But then why not just make that the default syntax, so that no migration is necessary, and only one syntax has to be learned/explained to people?
Because that syntax received significant boohs when I presented it at EuroPython. --Guido van Rossum (home page: http://www.python.org/~guido/)