The first reaction is to say "What IT department"!

By 2015 or perhaps a year or 2 later, the notion that an IT department will stand alone in enlightened organisations will look ludicrous. IT as a function will certainly disappear - Cloud Computing sees to that. However there are still a great number of jobs needed.

Network, Desktop, Apps and Systems support and config have all but disappeared in this timeframe. Deep engagement with business units has strengthened and business analysis is still needed to help users define their needs. Those needs are satisfied by commoditised solutions offered by the Cloud. Much more emphasis on business architecture and contract management, with user support incorporated into general business support function ( and probably outsourced).

I'm afraid by the end of the decade, IT departments are as relevant as large scale coal mining in the UK.