If you want to see the Places menu of that of Ubuntu 10.10 on Oneiric or Natty, you can do this with the help of the Places-Indicator, which shows in the Unity top panel your common folders (Documents, Computer, Pictures, etc.) and bookmarks.
Places Indicator Installation
To run the Places Indicator on Ubuntu 11.10 (Oneiric Ocelot) or Ubuntu 11.04 (Natty Narwhal), download it first from here. Then, unzip the archive file and double click "indicator-places.py" to start it. It will look like this on your top bar:
You can start the indicator automatically by adding it to Startup Applications.