I have started to become more aware of how disastrous my email box looks... If an email gets pushed to the "2nd page" on my long inbox list, it is sadly forgotten!
So - I am trying to take Jon's advice and keep it clean and organized.
You can watch Jon's presentation here.
The GMail Blog also has some great tips. These are two that I have just implemented and they work GREAT!
Inserting a Calendar invite directly from your gmail message.
Nesting your labels.