Sony Corp said on Wednesday that early demand for its latest electronic reader was higher than expected in advance of the holidays and shipment delays could result.

A Sony spokesman said the $399 e-book reader, called the Daily Edition and geared to newspaper viewing, would be sold on a first come, first serve basis.

The number of people that signed up ... to be notified of the Daily's availability exceeded our expectations over the last few months and we expect high demand now that it's available, the spokesman, Kyle Austin, wrote in an email to Reuters.

A notice on said that pre-orders will ship between December 18 through January 8, with no guarantee of delivery date.

The Daily Edition, Sony's first wireless e-reader, launched in August as a challenger to's Kindle, which analysts believe holds top market share.

Other devices sold by Sony -- the smaller $199 Pocket Edition and the $299 Touch Edition -- do not include wireless.

Amazon offers a $259 basic Kindle and a larger-screen version, also geared to newspaper and magazine viewing, for $489.

Industry experts believe that electronic readers sold by Amazon, Sony and new rivals such as Barnes & Noble and others will be top-selling electronic gadgets for the holidays, but manufacturers do not release predictions.

(Reporting by Alexandria Sage, editing by Leslie Gevirtz)