Apple's iBook went straight to number one as the best-selling notebook in US retail, online and mail-order channels last month, according to PC Data's latest figures. The upshot was a near doubling of the Mac maker's market share in the mobile arena, up to 11 per cent from 6.5 per cent in September. Not bad given the effects of the current LCD famine and last month's earthquake in Taiwan, home of most of the world's notebook production. Those problems will, of course, have hit all notebook manufacturers, but it's clear that Apple's $100 million pay-off to Samsung to ensure a solid supply of displays has helped to ensure that it has been able to meet demand for iBooks. Dell too has paid Samsung, this time $200 million, to make sure it gets sufficient screens. As an exclusively direct vendor, Dell isn't included in PC Data's numbers. Of the companies whoare factored in, the iBook's boost to Apple's mobile market share puts the company in fifth place behind Sony (13.9 per cent), IBM (15 per cent), Toshiba (26 per cent) and Compaq (27.5 per cent). Given the absence of Dell's direct sales from the stats, it's not clear whether Apple's (or anyone else's, for that matter) direct sales are included or not. Even if they are, Apple still has some way to go if it's to regain a position in the top three. It will be interesting to see how iBook sales develop over time. The iMac went straight to number one, and has spent most of the intervening time in the top slot or within the top five. Only of late has it slipped out of the top five, though the introduction of new, faster models last month should have given the machine a boost. Unlike the iMac, however, the iBook has been heavily pre-ordered. While PC Data claims that most of the sales it recorded in October were for real sales -- the buyer got to take product away with them, in other words -- rather than pre-orders, it's not clear how many of those real sales were thefulfilment of pre-orders. If so, iBook sales could drop off rapidly, once initial demand has been satisfied. Apple, of course, is banking on iMac and iBook sales over the Christmas period for another record-breaking quarter, something that's particularly import to achieve after the last quarter's better than expected but still below par results. ®