Does this prove that patch 2.4 is tomorrow? Nope. For one thing, I've had the entire patch downloaded for the past few days according to that there background downloader widget you consarned kids keep jawing about. In my day, we didn't have background downloaders! We just downloaded patches and we liked it that way. It's entirely possible Blizzard has released the same patch to download sites just to ease its release without intending it to go live tomorrow.
Still, it seems like a strong hint that tomorrow is the day, as both John Patricelli and I speculated when asked on the WoW Insider Radio Show two weeks ago. If the downloader has already downloaded, and now we're seeing the patch on sites, it doesn't seem like it can possibly be too far off. I'd bet a surprisingly small amount of money (due to my parsimony) that tomorrow is patch day. I hope your addons come through it with minimal scathing.
Thanks to Joel for the tip.