A major upgrade of your OS is always a leap of faith. In this case my upgrade from Ubuntu 7.10 (Gutsy Gibbon) to 8.04 LTS (Hardy Heron) was a smooth transition with no worries. Below is my walkthrough upgrading the OS which I have dual boot with Windows XP. Hardy Heron is indeed a slicker version of what is already a great linux distribution. Here is the step by step process in upgrading.
As always keep in mind the following before you do an upgrade of this magnitude:
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