In 2005 I bought a 420EX Speedlite on Amazong for $175 (new from Amazon). Tonight I was helping my friend look for a Flash for her 30D and the exact same flash is now $290 from Amazon. What's up with that?!
Inflation?
There's a lot more to new flashes than just a light bulb. They have intelligent processing that pre-fires a flash to measure the amount of light before the camera ever releases the shutter. This light is evaluated and then when the camera releases the shutter, the flash is adjusted to give the best exposure.
So, while flashes from a few years ago may be cheaper, the new ones of today have more technology, and thus, higher prices.
Curiously is there a big difference between a 420EX and a 430EX, besides the name of course I don't mind upgrading my gear but at times companies put out "new" devices with minor changes and usually a price increase.
Ed
Wow I was looking forward to getting the 580, but this may just do the trick! Sadly, it can't act as a master