The Good:

It's fast.

Hardy Heron is a fast, exceptionally stable operating system. It is a significant step up from Windows XP and better than Vista when it comes to efficiently using resources, and frankly, ease of use.

I've noticed that Hardy runs faster than its predecessor, 7.10 "Gutsy Gibbon." Firefox 3, which is the default web browser, is a major improvement to the solid Firefox 2.
It's more stable.

The Bad:

Suspend and Hibernate are still problematic.

Suspend and hibernate functionality is a basic requirement for mobile users and if Ubuntu is ever going to be a serious competitor for both home users and business, developers are going to have to make improvements to these areas a priority.

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