I didn’t go, of course (next year hopefully), but I can live vicariously through slides!

Ilia Alshanetsky had my favorites:

• Securing PHP Applications (.pdf) – Comprehensive with good examples. If you read Chris Shiflett, there won’t be a lot new covered, but still a good read.
• PHP & Performance (.pdf) – Again, covering all the bases with some real eye-openers. The kind of stuff Python devs find contemptful allows you to squeeze massive performance out of PHP. I like both schools of thought: elegance when possible, brute optimization when it heats up.
• Security Pitfalls (.pdf)

Also Jeff Moore’s presentation on the Dependency Injection (.pdf) pattern.

Derick Rethans (of eZ Components) has quite a few great presentations archived (though several are duplicates), including the best overview I’ve seen of PHP 5.2’s new native Date and DateTimeZone classes (.pdf) (and why date handling can be such a mess without them).

Phalanger is a .NET compiler for PHP5. Yes, PHP code compiled into CLR running on .NET (or Mono), with access to .NET classes as PHP objects (!), and apparently running almost twice as fast as on the PHP CGI. And they’ve implemented enough native PHP functions identically enough to run fairly extensive apps (MediaWiki, WordPress, phpBB3) out-of-the-box. There are a couple PDFs in the docs that describe in intimate detail the intracacies of wrapping .NET objects so they behave as PHP objects do and vice-versa; the team knows the PHP5 object model inside and out and they’ve extended the syntax to allow importing namespaced .NET code.

The benchmarks look impressive (almost double the performance on phpBB), but certainly using a opcode cache or running on Apache or lighttpd would level the performance a bit. Then again, why would you use Phalanger just to run all native PHP apps? I guess if you’ve done a lot of PHP development and been itching to try out .NET, this is something to look into.