The Panasonic PT-AE3000 officially comes with a one year, parts and labor warranty. Currently, Panasonic is offering a second year via a mail in rebate offer. How long that will stay in effect is unknown.
By comparison, the 1080p resolution projector competition mostly offers two years parts and labor, with some offering three years (BenQ on the W20000, Epson on their Pro Cinema projectors). Optoma offers two years, except, I believe, on the HD81-LV, a far more expensive projector. BenQ provides one year on their W5000. Mitsubishi offers two years.
A few projectors have overnight or 48 hour replacement programs, including Epson for the full two years - Home Cinema series, and for three years on their Pro Cinema series. BenQ offers a one year replacement program.
As long as the two year warranty program is available on the PT-AE3000, I consider it a good, but not exceptional warranty. If the program ends, and the warranty drops back to one year, then, not so good.
As projector repairs tend to be expensive, I recommend buying a 2nd year warranty if Panasonic goes back to a one year warranty. While I'm not a huge fan of 3rd party warranties, at least not compared to manufacturer warranties, those third party warranties are pretty inexpensive. Go for it!