It's worse than that - on Feb 26th they increased their rates for texts to 10p & calls to 25p/min.

My wife & I are both very light PAYG users, so after several years with GiffGaff we've changed to Three - we know when we're not wanted! Having said that, I'm still using GiffGaff as I'm taking advantage of the fact that if you visit their online community you earn payback credits; my credit still stands at around £60 despite my not having paid a penny for over three years! We both have dual-SIM phones, so we're able to keep both SIMs active - GiffGaff is cheaper for some things.

We've also stopped the unlimited calls option on the landline, so all our outgoing calls are on mobiles as its cheaper. Then there's Skype! The upshot of all this is that I've had to set up a spreadsheet showing the cheapest option for all the calls we're likely to make!