But companies should look closely at the ROI calculation: plenty of workers don't travel enough to warrant US$600 a year for 3G data service, especially with Wi-Fi hotspots and Ethernet access at many hotels priced at $10 to $20 per day, and sometimes even for free. But Dulaney's April report noted that Verizon Wireless offers a US$15 pay-as-you-go data service for laptop users, worth considering as an alternative to Wi-Fi plans.

In the United States, mobile carriers are scrambling to expand their 3G scope and reliability, including better indoor coverage. The reach of those networks, their actual throughput (which is shared by users linked to a given cell), and reliability can as a result vary widely. Enterprise IT executives need to know the requirements of their mobile end users, and map these to the devices, service plans and infrastructure costs (including device management, security and support) needed to satisfy them.

Those infrastructure costs, including business process re-engineering, could be substantial. Today's IT infrastructure is optimized for desktop productivity, Mathias says. Re-orienting to optimize for mobile productivity will be a "fairly large shift in thinking," he says.