A very good place to work, if you can handle New England winters.
Pros: management is largely compsed of developers, wonderful culture, extensive lunch offerings within the building itself and the neighborhood at large
Cons: snow! and ice storms! some communication difficulties within the office, occasional issues with noise level
The most impressive aspect of Priceline that I saw was the infrastructure. There was a well-developed, thoroughly-tested infrastructure, in terms of software, hardware, and even personnel and policy. The software infrastructure was not always well documented, but that was less problematic than usual, as there was a better than ninety percent chance that the developer who built any arbitrary component was still around to ask about it.
Hours were flexible, telecommuting was frequently an option (and heavily recommended in inclement weather), and vacation time was plentiful (as a new employee, I accrued 18 days of vacation a year, anyone who stayed six years would receive 24 days). There were some snags, developers could expect calls at three in the morning if their code broke, the noise level in the office became problematic on occasion, and there were known bugs in intra-office communication. All in all, though, these issues were minor, and the company was actively working to remedy the last two (the first rather comes with the territory when coding for high-availability web services and pages).
The only factor that drove me away is completely beyond the company's control: snow. If one is accustomed to frequent and heavy snowfall, this likely won't be a factor at all. If, however, one hails from a warmer climate, it can be most troublesome.