Following Sprint’s lead, Verizon tests $70/month unlimited data bundle

Shortly after shaking things up with a bargain $15-a-month data plan, Verizon Wireless is testing out a new unlimited mobile bundle that'll sound familiar to anyone who subscribes to Sprint's $70/month "Everything Data" plan.
First reported by the Boy Genius Report and now confirmed by the Wall Street Journal, Verizon's latest deal — which offers unlimited text mesasges, data, and mobile-to-mobile calling for $69.99 a month — is just a "selectively distributed discount" for now.
That means the bundle, which also includes 450 standard voice minutes, isn't open to just anyone; you'll have to be the lucky recipient of an email offer from the carrier, which is describing its latest mobile plan as a customer "retention tool," the Journal reports.
The Boy Genius Report has a screenshot of Verizon's email offer, which also includes a $139 family bundle with the same unlimited text messages, data, and mobile-to-mobile minutes, along with 1,400 voice minutes.
Both of the trial Verizon plans require that you extend your mobile contract for another year, Boy Genius adds.
Verizon's new unlimited mobile bundles bear a striking resemblance to the "Everything Data" plans on Sprint, which offer unlimited data, messaging, and mobile-to-mobile minutes (including calls to cell phones on other carriers), plus 450 regular voice minutes, for — you guessed it — $69.99 a month.
Sprint also offers an individual "Everything Data" plan with 900 minutes for $89 a month, along with a pair of unlimited family bundles: one with 1,500 minutes for $129 a month, and a second with 3,000 minutes for $169/month.
Verizon recently began tinkering with its smartphone data offerings, launching a $15-a-month plan that includes 150MB of data late last month.
The deal is set to expire at the end of December, Reuters says, but it's always possible that Verizon will keep the plan around. Verizon is hanging onto its existing $30-a-month unlimited data plan for smartphones.
Meanwhile, the other big mobile carriers are slowly but surely picking off their unlimited 3G smartphone data offerings.
AT&T did away with unlimited 3G smartphone data (except for subscribers who've been grandfathered in) back in June, right before the launch of the iPhone 4, while T-Mobile announced in October that it would start "throttling" users who exceeded 5GB of 3G data a month.
Of course, tiered data plans like those offered by AT&T ($15 a month for 200MB of data, or $25/month for 2GB) might make sense for mobile users who aren't using that much data on their phones. Fans of streaming video, however, will probably blow through such 200MB and 2GB data caps pretty quickly.
So, what do you think of the $70-a-month unlimited data bundles offered by Sprint and (now) Verizon? Sound like good deals? Or would you rather pick a cheaper data plan with a cap?