I registered my own domain about 4 years ago so I'd never have to change my email address again; it happens to be a .net. Now I face what amounts to a retroactive price hike.
Speaking of nothing practical to add...
How is this retroactive? You're not being asked to pay more for the last 4 years you were registered. You can lock in prices now with a longer term contract. You sign a 1 year contract every year for a .net domain, and lock in the price for that year. It's just like cell phone service, cable TV (really, more monthly), and every other service you get provided.
Show me where you were ever guaranteed that your prices would stay the same, and then you can start complaining. Or heck, wait until VeriSign actually decides to raise prices. Right now it's just ICANN saying that they can. Chances are, if they do raise the prices they'll just raise them to $6 per domain per year, like the .com domains. And since most registrars currently charge you the same fee for .com and .net, you're actually getting "screwed" now.