AOL, Microsoft and Yahoo! are partnering to cross sell non-guaranteed display inventory in the US, highlighting their need for scale in the face of increasing competition from Google and Facebook

Aggregating unreserved ads via their respective networks may boost share of ad budgets, but the focus on less valuable inventory means any impact is likely to be small

Short of extending the partnership to include all inventory and greater investment in technology there seems little the three companies can do to stop further erosion of display share, though revenues should continue to rise

In this report we outline the current state and likely development of the war between mobile platforms. We discuss installed bases and activity levels, the key issues facing Apple and Android, including Android fragmentation and Google's acquisition of Motorola, and go on to look at the tablet market and the outlook for RIM, Nokia and Windows Phone.