I guess I think it'd be interesting to see what other's think. Also,
another point to check is if list() can also be converted into 
because having a hybrid wouldn't be too nice.
Having list() work the same way would be very sexy indeed:
[$a, $b] = [$b, $a];
To be honest I never really liked the distinction between list() and
Using  for arrays is also consistent with dereferenceing arrays and
therefore shouldn't confuse people really.
My first shot at extending the parser to allow  for list() failed
though as both T_LIST and T_ARRAY are used in expr_without_variable. But
I'm sure you could find a clever way around this, my knowledge of yacc
is still limited :-)
But even without  for list() I think  for array() would be nice ;-)