I believe the Kindle Books can be read on any device with the availability of the Kindle Reader software. 
My wife wanted a Kindle and I told her: "You already have an iPad, use that :-)"
It seems to work nicely, but you're right on the spend difference. 
My personal preference would be to read books on a device I already have rather than buy a brick just for reading books. 
I already carry too many devices and a Kindle just seems like one too many more :-)
Regards,
Richard Schoen
RJS Software Systems Inc.
Where Information Meets Innovation
Document Management, Workflow, Report Delivery, Forms and Business Intelligence
Email: richard@xxxxxxxxxxxxxxx
Web Site: 
http://www.rjssoftware.com
Tel: (952) 736-5800
Fax: (952) 736-5801
Toll Free: (888) RJSSOFT
------------------------------
message: 5
date: Thu, 23 Dec 2010 13:14:02 -0600
from: BMay@xxxxxxxxx
subject: Re: [WEB400] PHP Books at Sitepoint
Mike,
I can definitely recommend the Kindle.  And it won't break the bank as 
much as the iPad.  WiFi only version of the Kindle is only $139.
Brian May
Project Lead
Management Information Systems
Garan, Incorporated
Starkville, Mississippi
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