Market watcher Canalys has bullishly forecast that Apple will begin to ship more personal computers than current market leader HP at some point during H1 2012.

The caveat: you have to include iPad shipments in the total.

Apple could out-ship HP during Q4, Canalys reckons, but it admitted the fruit-flavoured firm may have to wait until the iPad 3 is out - the new tablet is expected mid to late Q1 2012.

Canalys estimates full-year 2011 global PC shipments to reach 415m units, up 15 per cent year on year, thanks predominantly to growing tablet sales.

Total tablet shipments are expected to reach 59m units by the end of the year, with fourth-quarter volumes predicted to exceed 22m units.

Laptop shipments will hit 211m units in 2011, Canalys said, a year-on-year increase of ten per cent. Combine that total with that of the tablets and you'll see that 65 per cent of the personal computing devices that shipped in 2011 are mobile machines.

The release of Android 4.0 Ice Cream Sandwich appears to have come too late for vendors to use the OS update to launch Christmas sales drives. The ICS-based tablets that have been announced so far are all out early in 2012.

Geographically, Canalys reckons North America will account for 103m PCs in 2011, 18 per cent up on 2010. Almost all the growth comes from tablets - shipments would be up less than a single percentage point otherwise.

In Europe, growth would be down six per cent if it wasn't for tablets, but with a small rise if tablets are included. ®