The ALM Rangers just released the v3 of the TFS Upgrade Guide. Apart from the official announcement, etc., I wanted to give you a valid reason to download and use it if you are still sceptic.
Scenarios. This guide covers a handful lot of real world scenarios, like the upgrade from 2008 or different configurations. So it is not just a basic walkthrough, but it provides you a robust sample from people who already experienced the aforementioned scenarios.
Give it a try, you won’t regret it ;)