The signature guidelines for all boards has been revised (July 2010). Please take a minute and review them:
One of the main concerns is the overall size. Please remember that we are all limited to 500x500 pixels maximum, with a file size limit of 250kb maximum. And this DOES include any tickers you have in your signature.
If you have any questions or need help with your signature, you can visit the Signature Help board where Christy (Mom2ThreeKiddos) is always quite happy to help anybody who has any questions, concerns, etc.
Thanks for your attention to this matter.