Useful links for upgrade from Sharepoint 2007 to 2010

Here I would like to provide useful links which I found during investigation of the upgrade process from Sharepoint 2007 to Sharepoint 2010. I’m planning to update this post in the future with more resources. Currently there will be links from official MS technet guide which are located in various places. For convenience I summarized them in one place as flat list:
Upgrade and Migration for SharePoint Server 2010 – starting point for investigation
Determine upgrade approach – describes 2 possible upgrade strategies: In-place upgrade and Database attach upgrade
Upgrade process overview – contains steps which should be performed for both types of upgrade
Review supported and unsupported upgrade paths – information about supported source and target topologies for upgrade
Hardware and software requirements – software and hardware requirements for upgrade to  Sharepoint 2010
Use a trial upgrade to find potential issues – describe process of test upgrade which should be performed prior to make production upgrade for searching possible issues
Microsoft SharePoint 2010 Products — Test Your Upgrade Process – Visio poster with upgrade schema
As I said I’m going to update this post in the future and use as a reference in forums threads where people ask about upgrade process.