As you probably have read regarding the SharePoint SP2 bug which reverts your license to the trial license which would expire after 180 days, and causes your existing license to expire in 180 days after the upgrade.  You could have fixes the problem by re-entering your license key into the system.

Microsoft has released a fix for this, this could be applied before or after the SP2 upgrade.

The 32-bit version can be downloaded here.

The 64-bit version is here.

For more information, you can read the kb article here:  http://support.microsoft.com/kb/971620

Service Pack 2 for Office System 2007 and Office Server 2007 has been released on April 28th.

For more details on what is in the Service Pack 2 could be found here:

• Description of WSS 3.0 SP2
• Description of MOSS 2007 SP2
• Description of SharePoint Designer 2007 SP2

More information could also be found at Updates Resource Center for SharePoint Products & Technologies

There is no media for the SP2, below are the links to download the binaries:

• WSS 3.0 SP2
• MOSS 2007 SP2
• SharePoint Designer 2007 SP2