Ubuntu 11.04 beta 2 has been released with few packages updates and better performance than earlier releases. Check this post for Ubuntu 11.04 beta 2 release notes, Download links also upgrade instructions from Ubuntu 10.10 Maverick to Natty Narwhal beta 2 included on the release notes.

Use this distribution at your own risk. It’s not recommended to use it in production machines.

I used Ubuntu 11.04 beta 2 as a live session on USB flash disk also installed it with these hardware specifications 2.1 Ghz dual core processor, 2 GB of RAM, and 265MB video card memory.