The new iPad launched supporting both AT&T and Verizon, as it did with the previous model. The big difference with carrier support with the third-generation offering was the addition of LTE to both devices. For the AT&T version, it was business as usual, only faster. But to support LTE with the Verizon model, a SIM card had to be added to the device.
GSM carriers and its users have enjoyed the flexibility of a SIM card for years, with the ability to switch between devices by simply removing their SIM from one device and placing it in another. CDMA users have had to call and request an ESN change each time they wanted to switch devices. This is beginning to change for Verizon users with the continued rollout of LTE (a GSM-based network), and the SIM requirement.
This got me wondering: what if I activated a data-only plan in the Verizon iPad, would I then have a data-only plan for a smartphone?
So I activated my iPad with the 1GB plan, waited for the confirmation everything had gone through, and then removed the SIM from my iPad. I put the SIM in my Verizon Galaxy Nexus, and immediately saw a data connection. I then tried to place a call from the Galaxy Nexus and it didn't go through. Instead, I was prompted to add money to my "prepaid account". It literally is a data-only-plan. One thing to note, however, is that the hot-spot feature included with the iPad plan does not work on the Galaxy Nexus.
After doing some more testing with the SIM in an LTE market, I wasn't able to get my Galaxy Nexus to connect to Verizon's LTE network (only its 3G network), while the iPad would connect to LTE without issue. I assume this has to do with provisioning on the SIM card, and the Galaxy Nexus not being allowed to connect to Verizon's LTE network. In the end, you may miss out on an LTE connection, but you will still have a data-only plan.
The credit card used to sign up for service will automatically be charged one day prior to the plan's expiration date (one month from the date you signed up). You can cancel at any time by calling Verizon, or putting the SIM back into an iPad and canceling through the Cellular Data menu.
For some, having a voice plan in addition to a texting and data plan isn't a big deal, but for those who prefer to carry two devices or never talk on the phone, the additional voice plan is a waste of money. By activating a SIM card in an iPad, they eliminate the need for any additional charges, as well as any contract that would normally be associated with a new plan.
Update, 7:31 a.m. PT: Updated post to include note regarding the Galaxy Nexus not connecting to LTE when using the iPad SIM