It was back in November when we told you for the first time that the Dell Venue Pro may be delayed until January, but the official information on the Dell blog doesn't elaborate on what caused the delay. It says:
"Dell is ramping production as fast as we can. We’re continuing to monitor our manufacturing and supplies and will make every effort to align shipments with arrival expectations. At this point, our most important focus is to deliver the right out-of-box experience so customers are happy with their purchase.
It is true we recently experienced a slight delay in shipment times. Those delays will affect some customers shipping dates. We will be following up with many of you directly. The January 6 date that's being reported could be correct for some but not all, as ship times vary by customer and the date/ time that they placed an order."
source: Dell Official Blog via SlashGear.com