While trying 3.3 beta I found that I cannot use my favorite virtualenv pattern with pyvenv:
$ virtualenv . Installing.....done.
$ pyvenv . Error: Directory exists: /Users/stefan/sandbox/foo
I appreciate that this behavior is documented and was in the PEP from the start: "If the target directory already exists an error will be raised, unless the --clear or --upgrade option was provided."
Still, I am curious what the rationale behind this restriction is. For me, being able to "bless" an existing directory with a virtualenv has always been one of its attractions.