On the Ibuildings blog today there's a year in review post (from Ben Longden, Rowan Merewood and Alistair Stead) looking back at 2011 and everything that happened in the world of PHP.
2011 has flown by in a blur as we have been busy helping many new clients with large scale PHP projects - proof that PHP continues to gain traction with enterprise. [...] The ongoing financial climate only adds pressure for IT managers to cut costs and deliver more value from their existing infrastructure and therefore require enterprises to re-consider any prior aversion to open source and PHP. This is allowing our industry to consistently buck the trend of the markets and expand to support the increased demand.
They list some of the changes in PHP itself, like the Release Candidates for PHP 5.4 and the 5.3 requirements of some frameworks, as well as some community-related changes: Facebook's Virtual PHP Machine (hhvm) and the number of PHP-related events in Europe and the UK. They mention some projects that become more prominent in 2011 including BDD testing, Platform as a Service products and the EBay acquisition of Magento.
Also included in the post are a few predictions for 2012 including a possible merging of frameworks along similar strategies, the increased use of dependency injection containers and a serious look into caching in PHP applications.