PIX is dead. Long live PIX.
So Cisco just announced the end-of-sale for the PIX product line. This was not unexpected. Ever since Cisco announced the ASA product family, it was clear that the PIX was on the chopping block. Cisco will stop selling PIX products immediately but will continue to support them through 2013.
Customers who were riding the PIX bandwagon and are now faced with a decision might want to look at Vyatta or other solutions. While the ASA is a reasonable product, Vyatta can deliver far more flexibility over time without the threat of proprietary lock-in prices for upgrades and expansion. Where Cisco charges for each and every add-on, Vyatta includes far more functionality in the base product and has more headroom. Further, hardware expansion is a fraction of what Cisco charges, even when they allow you to expand at all.