Note that there are a few sub-$1000 projectors with two years and even three year warranties out there. That said, the only 2 year I can think of right at the Viewsonic PJD7820HD's price point is Epson's HC750HD, but consider that the Epson is only a 720p resolution projector.
With one year warranties, I suggest you consider an extended warranty, or purchasing your projector with a credit card that offers an extended warranty. A problem after two years, you likely can buy a better projector for less, minimizing any financial setback.
Although I have little to report about Viewsonic's support after sale, I can say from my level of contact - with marketing, PR, and product management folks I work with, Viewsonic is an extremely responsive company. If that level of support carries over to consumers, then I would say that they have superior support, but that's just me connecting the dots.
Bottom line on warranty: Could be longer, but solid for the price point! And if you do need warranty service in the first year, you'll likely love that they offer express replacement!