They also stopped supporting PHP 4.4 which means hundreds of thousands of legacy installs no longer do automatic updates because their update code (purposely? lazily?) has a few lines that don't work under PHP 4.
IE6 is one thing to go "meh" about but WordPress installs that do not do fast easy updates are time bombs.
There's nothing lazy about not supporting PHP 4. It is outdated and flawed, and the last release was in 2008. PHP 5 has been out for over 5 years. The fact that those sites are timebombs is not WordPress's fault or their problem.
But WordPress is an "ancient" legacy mess and does not have any advanced code that benefits from PHP5 - you actually have to go out of your way to break it for PHP4. There is nothing in it that cannot be fixed for PHP4 without one extra line or two.
Note that 99.9% of WordPress3 works on PHP4 - only the security updating fails - and it fails in an uncontrolled way, not because it checks for the PHP version and stops - it actually fails silently (which is also typical WP style).
There are hundreds of thousands of shared servers that are still running PHP 4.4.9 just fine and WordPress has a responsibility to make sure security updates keep working if it's easy enough to maintain (and it is).
WordPress didn't end support until 3 years after PHP 4's end of life. I think that's a more than reasonable amount of time to wait before enforcing an upgrade.
The fact that WordPress does not have any code that benefits from PHP 5 is undoubtedly, in part, due to its extended support for PHP 4.
All the known issues with PHP4 and upgrading have been down to bad configurations of the servers, and quite often, insecure configurations of shared hosts. Often swtiching to their servers PHP5 support would "fix" it, simply due to the PHP5 configuration often being setup better than their legacy php.ini for php4 from when php 4.1 was standard..
> and it fails in an uncontrolled way, not because it checks for the PHP version and stops - it actually fails silently (which is also typical WP style).
Did you ever bother helping fix that? If it's failing silently it's either due to a timeout (often configuration related), php error (often plugin related), or http error (dodgy php configuration, or extension is malfunctioning - curl i'm looking at you!)
WordPress has usage stats of what servers are running, The majority of PHP 4.4 hosts have access to PHP5 through their hosts, they just have to turn it on. Most other major webhosts have been contacted and have plans to support php5 as well.
Every other major web application has made the move, It's time for webhosts to spend their customers monthly fee's on providing up to date, secure services, not just letting the server rot..