Well according to the confidentiality letter from HTC to FCC, HTC requested the FCC to keep the product confidential until April 30th 2010...so if it doesn't come by then, at least we'll may have an opportunity to see if anything has change but the radio.
Here's the letter. https://fjallfoss.fcc.gov/prod/oet/forms/blobs/retrieve.cgi?attachment_id=1242461&native_or_pdf=pdf
Are we sure that's for the Nexus One? It really gives no clues to what phone it's for, and the person that signed it is the "WM Product & Project Manager Dept" - could "WM" mean Windows Mobile?