gest challenge is the lack of interoperability between services and between handsets. Other major issues include concerns about privacy and ease of use. Finally, business issues also present problems, including usage cases, appropriate applications and content, negotiation of deals with IM providers, cannibalization of voice and SMS services revenues, and the cost of installing a presence server. Analysts suggest that the main application for mobile presence services will be in the peer-to-peer consumer segments rather than the enterprise market. Until there is widespread adoption of mobile IM/presence by users, it is unlikely that it will be used with any significance as a medium for business-to-consumer communication. Mobile Gaming Mobile gaming is definitely more than a fad. In recent times, mobile games have grown increasingly popular as a means of providing personal entertainment on the go. According to a 2006 eMarketer report (www.emarketer.com/Report.aspx?mobile_ gaming_feb06), worldwide revenues for mobile gaming reached US$2.5 billion in 2005 and are projected to top US$11 billion by 2010. eMarketer also cites recent IDC (www.idc.com) numbers that show U.S. revenues from mobile games rising to US$1.5 billion in 2008, from US$600 million in 2005. The study further finds that Mobile Gaming nearly half of all free mobile game downloads are for puzzle and card games, pro- ducing over 25% of all mobile gaming revenues. Part of the reason for the popular- ity of these simple games comes from the impact of the limited screen size navigation options of the mobile handsets, but as the devices become more sophis- ticated, so will the type of games users engage in. With the number of mobile gamers around the world growing, with some esti- mates predicting 220 million global users by 2009, the mobile gaming business is projected to expand and be a bigger portion of the profit pie for the cellular carriers and handset makers. However, aside from the value of the revenues earned from games sales, there is additional p