We’re still waiting to hear from Palm or Sprint as to how many Pre smartphones were sold this weekend, but early estimates from J.P. Morgan analyst Paul Cooster suggest sales in excess of 50,000 units.  Low initial stocks – as warned by Sprint CEO Dan Hesse – may have contributed to a sell-out weekend.

“We conclude that the launch of the Palm Pre has probably been successful. Sales in the first two days probably exceed 50,000, which aligns with our expectations, but sales are very probably short of the 146,000 reported for the first generation Apple iPhone, owing to capacity constraints in manufacturing (or imposed by PALM’s balance sheet). We believe the ’soft launch’ is probably proceeding to plan. To be reassured, we need to see Sprint channel inventory replenished this week.” Paul Cooster, analyst, J.P. Morgan

While Palm is yet to confirm what caused the shortage, numbers of Pre devices varied widely across different locations.  Flagship Sprint stores reportedly had up to 200 handsets, though 30 to 50 was more usual, while other locations made do with less than 10 Pre devices according to feedback.  The Touchstone inductive charger, an accessory Palm suggested every Pre owner would want to buy, turned out to be in surprisingly short supply, more so even than the smartphone itself.

Palm are believed to be preparing the next wave of stock for the rest of this week and in anticipation of next weekend’s sales.  Demand will likely be partially dependent on Apple, who are expected to announce a new iPhone at their WWDC 2009 keynote event today in San Francisco.