For me it's much more usable than the overblasted, Eclipse (*blearch*) based Zend Studio.
A feature I'd really love to see is an overwriting of autocompleted )'s and "'s etc.
Like you have it in Whole Tomato's Visual Assist Plugin for Visual Studio.
You open a brace,
...foo(...
VS adds the closing brace with the cursor in the middle...
...foo(|) ...
you enter the parameter...
...foo(7|) ...
and by closing the brace manually you don't end up with
...foo(7)|) ...
but with
... foo(7)|...
as the closing brace is overwritten.
I think, the logic behind is simple: "You can't add a closing ')' while inside and at the end of two braces. => (bla bla bla bla |)
autocompleted braces and quotation marks are a great thing when entering long expressions...
but when entering short parameters it's (for my brain) much more intuitive to be able to type quickly (-7-) than (-7-END.
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Another point on my wishlist would be:
I'm an excessive user of autocomplete.

Reduced autocomplete delay to 0ms and... it's wonderful.
It would be just nice to see the cursor landing between the braces of a function after autocomplete when the function needs arguments.
massive_foo_function(|) instead of massive_foo_function()|
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Oh... and one more came in my mind:
No autocomplete while editing inside code.
Most of the time the popping second " is not what I want when editing a line...