pyvenv in Python 3.3 was immensely frustrating to use, because it leaves you without any package manager that understands your virtualenv.
I've seen this rumor that virtualenv "doesn't work" in Python 3. It seems to be propagated by people who make Python 2 virtualenvs and get confused, including a StackOverflow thread full of people basically typing commands at random to try to fix the problem. But pyvenv in 3.3 had much more potential for confusion.
The fact that Python 3.4 bundles pip may finally resolve this confusion, and make pyvenv appropriate to use. But I'm sure virtualenv will keep working fine as well as long as you don't mix up major versions of Python.
Yes, the regular virtualenv may work with Python 3 but it's a small detail in a frustrating setup. When I finally found out how you're supposed to do in > 3.4 it was a relief, still
Just tested 3.4 as it is like in 2.X, so, problem solved and no-one has to worry about this anymore.