Back in August, Verizon split its unlimited data plan into three separate plans - Go Unlimited, Beyond Unlimited, and Business Unlimited. All three plans have limitations on video streaming, tethering, and international usage. But starting on January 25, Go Unlimited will include limited service to Mexico and Canada.
Verizon told us in a statement that all Go Unlimited customers (both new and current) will have unlimited talk and text to/from both countries. Since this is Verizon we're talking about, there is still a catch - you only get 500MB of 4G LTE data per day, then it drops to 2G. For comparison, both T-Mobile's and AT&T's plans already include unlimited talk and text in both countries. Roaming LTE data is limited to 5GB/month on T-Mobile, and AT&T disables roaming entirely after 50% usage for two consecutive months.
Still, having limited connectivity while traveling in another country is far better than nothing. You can find more information about Verizon's plans here.