The Wall Street Journal claims that both Sony and Nintendo are in talks with wireless carrier NTT DoCoMo about integrating 3G mobile connectivity into upcoming handhelds.
In Nintendo's case this is believed to be an unannounced iteration of the not-yet-released 3DS. In Sony's case it would be for the still secretive but certainly in development PSP2.
It's becoming increasingly commonplace for portable devices aside from mobile phones to include 3D wireless support – just look at the Apple iPad or Amazon Kindle e-reader. And as WSJ points out, an always-on net connection drastically increases the potential for platform holders to make more money more often from over-the-air purchases.
Nintendo has already vowed to do something new with the online offer for the 3DS, recognising that its current network efforts have failed to deliver in some areas – most notably those involving ecommerce.
The WSJ's details on Sony's 3D involvement are more woolly, claiming that the company is developing a portable device that shares characteristics of hand-held game machines, e-book readers and netbook computers, according to people familiar with the matter”.