Photoshop: batch resizing for web

"I haven't done any batch processing in Photoshop in a while, so I can't comment. What I want to share is that if for some reason you aren't able to do what you need via batch processing, Photoshop can also be scripted via AppleScript, VBScript, and Javascript.

Here's an article about Photoshop scripting. Here's Adobe's current documentation. If you need older docs, you'll need to google for them."

I know this isn't helpful (Why are you writing the answer then ?), but such things weren't, for a fact, available in older verions of photoshop (around 4). I don't know about the newer ones, but I usually gave up on photoshop, and started using Imagemagick tools for anything remotely similar. Install them once, you won't be using them too often, but every once in a while, something like this will pop up, and then, they'll be a lifesaver.