Have you received the email from DreamHost saying your account has been approved? Also did you receive an email regarding your domain registration, if you registered one during the sign-up process?
Account approval can vary quite a bit, with some accounts being approved almost immediately and others taking a while.
Sometimes the application gets flagged by the DreamHost automated fraud detection system, which means it has to be manually approved. Exactly what causes an application to be flagged as potentially fraudulent is not readily apparent.
Anyway, my advice would be to give it a little longer (considering the weekend) and if nothing happens contact DreamHost to resolve the issue.
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