Isn't the Kobo going to be selling for $149 when it comes out in the U.S. next month? (I'm assuming you are in the U.S.) So if that extra $20 on top of the $30 makes a difference. Then again, you may not want to wait a whole month.
Also, if you don't care about a Touch screen (some people actually hate them), you could downgrade from the Sony Touch Edition to the Pocket Edition. That seems to be selling for about $30 less directly from Sony and $50 less elsewhere.
For example, Buy.com has it right this second for $149, including free shipping:
http://www.buy.com/prod/sony-prs300s...211584611.html
Ah, wait. That one is silver. If you prefer blue?:
http://www.buy.com/prod/sony-prs300b...211960207.html
Heck, Buy.com is never a place I'd normally look. They also have the Aluratek Libre on sale, for $129 shipped (I mean if unlike PodPeople you can't luck into one at Costco for $80).
http://www.buy.com/prod/aluratek-lib...211986386.html