IS recommended that you sync the time zone to the same of your sales/clicks reports if you have some. For example if you promote an affiliate program, use the same time zone of your affiliate program report: http://forums.digitalpoint.com/showthread.php?t=98696#6
I thought according to their TOS we can only have 1 Adwords account unless you pass their GAP program and get to use the client center? Do you really trace your name, company name or credit billing to make surey ou don't have multiple accounts? But when you promote multiple merchants, how do you decide which timezone to set for you Adwords?
Yes, Google does trace/track some of your information, including the credit card number you use to set up an account, as well as any URL's that you are directing traffic to with that account. If you get blackballed using an account, the credit card tied to that account as well as every URL tied to that account can never be used with AdWords again. I don't know if they keep track of stuff like name and address. You are in fact allowed to have multiple AdWords accounts, but you can't use separate accounts to direct traffic to the same URL, that's where you get in trouble. You are allowed to set up a client center without becoming certified.