Downloaded their ebook reader to try today. Verdict: Unimpressed. Mobipocket is better. I didn't bother with their reader for the iPhone. What turns me off are the prices. For many less popular titles their prices are way beyond what Amazon.com is offering. E.g., Snowball is $28.00 but you can get it for $9.99 at Amazon.com
Barnes and Noble would have to try harder to create a more compelling case to sell ebooks. They are probably more interested in making sales from their walk in customers.