The sony reader is a bit cheaper than the Kindle 2. However, I’ll still suggest the Kindle II, unless you are outside the US (as Amazon doesn’t allow order of the Kindle outside the United States) The biggest issue is the content availability. The Kindle is supported by Amazon with much more book selections. And Kindle books are cheaper than the actual books, so it will save you money in long term. In addition, Amazon provides thousands of Kindle books for free or at a low price. Sony reader is much weaker in this area.

There is a good comparison here about the two digital book readers:

http://www.speedreaderxreview.com/kindle-2-0-vs-sony-reader-prs-700bc-comparison

You may find interested in this review too:

http://www.amazon.com/gp/redirect.html?ie=UTF8&location=http%3A%2F%2Fwww.amazon.com%2Freview%2FR266PE1Q47CYNH%3Fie%3DUTF8%26ASIN%3DB00154JDAI%26nodeID%3D%26ref%255F%3Dcm%255Fcr%255Fpr%255Fcmt&tag=more_info-20&linkCode=ur2&camp=1789&creative=390957

Hope this helps.