Not every upgrade is a straightforward upgrade from one version of a product to the next. In order to help, we've got new TechNet library articles about how to perform an upgrade when you need to:
A frequently-asked question on the TechNet Forums is whether you can upgrade from Windows SharePoint Services 3.0 to SharePoint Server 2010. Yes, you can, and you can use a database attach approach to do so. This process is so straightforward, we didn’t need a whole article for it. Just follow the process for a database attach upgrade and attach your Windows SharePoint Services content databases to your SharePoint Server 2010 farm.
Another quick cross-product upgrade is from Office Forms Server 2007 to SharePoint Server 2010. Again, just do a database attach upgrade, being sure to transfer your form templates over. Everything you need to know is in the database attach upgrade content, and the article Plan to upgrade form templates during an upgrade to SharePoint Server 2010.
As always, let us know if you have any comments or questions!
Samantha Robertson, Senior Writer, SharePoint Products (I’m all about the upgrade)