After the initial burst of excitement on Friday that saw iPad pre-orders coming in at the rate of 25,000 per hour, there was a dramatic fall-off over the weekend. Friday was when the Apple device was available for pre-order.

According to Daniel Tello, the Venezuelan blogger-analyst who has been tracking order numbers submitted by volunteers at Investor Village’s AAPL Sanity board, orders on Saturday and Sunday slowed to an estimated 1,000 per hour — as reported by “Fortune” (http://brainstormtech.blogs.fortune.cnn.com/2010/03/15/apple-ipad-orders-drop-sharply/). Telloattributes roughly half of the estimated 120,000 first-day sales to “pure overexcited fanboism.”

The real demand for the iPad in the weeks before its April 3 release, is probably closer to 30,000 per weekday and half that on weekends, he told “Fortune.”

“With three weeks and two weekends left before they ship, I wouldn’t expect much more than half a million in pre-orders and reservations,” he says. “My best guess, although very tentative given the early stage and few data we have so far, would be that they hit the 1 million unit milestone by the second week after it ships. But this is a very speculative guesstimate based on just a weekend of pre-orders.”