The main reason for obfuscating the source is just to prevent casual gamers from being able to easily cheat in the game, since there's high score stuff for your guild.
Obviously, it won't prevent hardcore programmers from being able to cheat, but it is sufficient to stop most casual non-programmer types.
Blizzard have now added a deadline for when addons have to comply before they start taking action.
On March 20, we released the new add-on development policy to the public as an ongoing effort to help ensure add-on integrity, safety, and quality for the community. Since that time we have been in touch with many UI development communities on what the policy means to them and the continuing development of these add-ons. We would like to announce further that we are providing a sixty-day grace period beginning at the time of the initial release of the policy for UI developers to comply with the new policy. After May 19th, Blizzard Entertainment will begin to enforce the Add-on Development policy, and developers found to be in violation of this policy will be contacted directly.
Obviously, it won't prevent hardcore programmers from being able to cheat, but it is sufficient to stop most casual non-programmer types.
http://forums.worldofwarcraft.com/thread.html?topicId=16137620868&sid=1
I'm quite interested in how this is going to play out :p