Apparently, this is common, but I received the following form letter from Apple today:

Subject: iPhone Developer Program Enrollment Status

Dear Registered iPhone Developer,

Thank you for expressing interest in the iPhone Developer Program.  We have received your enrollment request.  As this time, the iPhone Developer Program is available to a limited number of developers and we plan to expand during the beta period.  We will contact you again regarding your enrollment status at the appropriate time.

Thank you for applying.

Best regards,

iPhone Developer Program

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