Unfortunately for those of us who hope for full grandfathering with no exceptions in the future, we will have to wait and see regardless of what VZ reveals on July 7. Like anything else, VZ could change its policy a year from now about grandfathering.
You can disagree with the philosophy about raising prices and complain about "corporate greed", but a corporation is in business to make profits and in fact has an obligation to its shareholders to make profits.
Second, if people in the long term are outraged enough to leave VZ, then VZ may have to adjust its pricing to compensate for the loss of customers. However, people are constantly coming to VZ from other carriers who are dissatisfied with service quality by other carriers and who already know that VZ plans cost more. VZ's new tiered data plans may not change the influx of customers much. For many people, the better service is worth it and for many people, their overall costs would decrease as a result of calling people frequently who are already on VZ, despite the new tiered data plans.
In the interim, I would not asssume that other companies will not make similar price increases. For a recent example in another industry, look at airlines charges for baggage, with only a few holdouts in the industry.
The cost of goods and services have risen in so many other areas of our lives that I believe it is not unreasonable to expect cell phone/data services to raise. We can nit pick the reasons why the carriers are raising their costs, but I believe we are all reasonably on notice that just about any cost we incur for anything may raise for some reason or the other. I am not saying that we should smile about it, though.