AT&T has adjusted its terms of service again — after retracting parts of a previous revision — to limit uses of mobile data plans for video services like Sling. The new change, as written up by DSL Reports today, excludes “redirecting television signals for viewing on Personal Computers.” Other things that continue to be prohibited on the service are downloading movies using P2P file-sharing services and web broadcasting.

What does all this TOS tweaking mean? Don’t expect to fire up your mobile data card on your laptop and overload it with video. (Confession: I watched ABC.com on Sprint EVDO while riding Caltrain a few weeks ago, and it was awesome.) The problem is, wireless networks are constrained by spectrum holdings, so they can’t just be beefed up to increase capacity like wired networks.

AT&T does have its own mobile video services, but these careful tweaks — narrowly targeting PCs instead of all wireless data — may help it avoid being seen as anti-competitive. But ultimately, there’s no such thing as net neutrality for wireless, so hopefully Sprint isn’t reading this. We’ll definitely be keeping an eye on the rollout of the Open Mobile Video Coalition later this year.

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