“Post-PC” is a phrase with many potential meanings, but one implication is that device preferences are changing. It isn’t clear yet whether growing sales of tablets, and declining sales of PCs, will have a material effect on global supplier revenue.

In other words, it isn’t completely clear that less money, or more money, will be made globally, by the whole industry, as tablet sales displace PC sales. 

Nor is it completely clear what the trend will ultimately mean for access service providers, either. One might argue that bandwidth demands could grow, but everybody expected that anyway.

Perhaps the biggest wild card is whether tablets lead to meaningful increases in consumption of video – particularly on mobile networks. 

That’s an indirect impact, but probably will represent the biggest impact of tablets for Internet service providers, perhaps positive for revenue, but also a potential negative in the sense of driving faster and more expensive network capacity upgrades.

Nor is it so clear whether greater volumes of tablets in use, compared to PCs, will materially affect demand for mobile broadband (dongle) accounts. That question is more complicated because of the growing use of personal hot spot capabilities in smartphones.

Demand for dedicated mobile broadband accounts is obviously reduced to some extent if a user can rely on the smartphone data plan to provide connectivity for a tablet or PC. On the other hand, the growing use of tablets also shifts demand.

It isn’t yet clear how much Wi-Fi offloading, use of personal hot spots and family or shared data plans will affect demand for mobile data. But there is little doubt now that sales of PCs are dropping globally, as the tablet trend takes hold.

In 2012, for example, global PC shipments dropped 3.7 percent, year over year, according to IDC.

IDC now expects 2013 PC shipments to decline by 1.3 percent as well.

Microsoft and Intel had been hoping that the Windows 8 launch would provide sales momentum, but IDC says that failed to happen.

Christmas and holiday sales were also disappointing, and information technology budgets were tight in the second half of 2012. All of that contributed to a year-over-year decline of 8.3 percent in fourth quarter PC shipments – the most substantial decline recorded for a holiday quarter, according to IDC.

Emerging market growth is also declining. 2012 was the first year that emerging markets saw a volume decline. IDC expects 2013 will see sales growth of less than 1 percent, continuing at about that rate through 2017.

In developed markets, 2013 will mark the third consecutive year of volume declines. IDC expects limited growth in 2014 and 2015 with PC sales declines in later years.

None of those trends yet are conclusively helpful or harmful for service providers, either fixed or mobile.