I don't remember hearing or reading anything about the cellular version outside of it being released "in the coming weeks". I don't think there was a specific date.
Speaking of which, if you have Amazon Prime you can order from them and for 8.99 have it delivered tomorrow (Saturday).
Amazon.com: ASUS New Nexus 7 FHD Tablet (7-Inch, 32GB, Black): Computers & Accessories
So I canceled my Best Buy pre-order and using the Amazon Prime trial, ordered it from Amazon with Saturday delivery. So here's hoping I get a tracking number today!
EDIT:
Apparently Best Buy is delivering some orders today and even selling them at local stores (might be specific locations).
Best Buy now selling the new Nexus 7, four days ahead of schedule | The Verge
I'm still keeping my Amazon order, ended up being cheaper since they don't charge sales tax and I can wait an extra day.