Monday 12th September 2016 Loaders updated for Raspberry Pi (ARMhf) and ARMel
Thursday 11th September 2014 Loaders updated up to version 10.1.3
Friday 20th December 2013 Facebook Porting PHP VM to ARM Architecture
While Facebook is remaining relatively quiet about the entire process, you can look at a far more technical explanation of their plans at their Hip Hop Virtual Machine blog here. If you're a highly-skilled PHP developer who is also very familiar with the ARM server architecture, you might even consider applying for the job!