This claim is ridiculous. Amazon's pricing is clearly designed to get you to store as much structured data as possible in S3, and simply to store references to that data in SimpleDB. If you follow that model, the pricing is very similar.
That isn't a claim, it's a simple observation that SimpleDB costs about ten times more than Google's datastore. You are absolutely right that SimpleDB is best used to return pointers to S3 data objects, and both the article and comments point out that actual costs depend on usage patterns. (Bandwidth costs will probably override database storage costs for many use cases.) Still, all the above doesn't change the fact that Google's distributed datastore is about a tenth the cost of Amazon's. You're just saying it doesn't matter in many usage scenarios.
Well, no, this is still misleading. One specific portion of the service costs 10x more, not the whole service. Furthermore, its the one part of the service that Amazon doesn't really expect you to use (hence the price).
As you said, storage is not likely to be the most expensive part of your database anyway, so claiming "Google's BigTable Costs 10 Times Less than Amazon's SimpleDB" is misleading at best.
Well, no, it's still accurate. Amazon's SimpleDB is a separate service. If you are trying to store a very large number of relatively small objects, like sessions or digg-like data, the S3 pricing doesn't come into it. Once again, it's not a claim that Google's datastore is a tenth the price of Amazon's SimpleDB. It's simple observation. If you want to say "Using Amazon data services is as cheap or cheaper than Google AppEngine" or add other services to the comparison, that's your prerogative. But the comparison of pricing for two services is not a claim and it's certainly not "ridiculous."
Claim: "Google's BigTable Costs 10 Times Less than Amazon's SimpleDB".
Fact: Structured data storage on BigTable costs 10 times less than structured data storage in SimpleDB.
Those two statements are not the same. Implying they are is very disingenuous.
"But the comparison of pricing for two services is not a claim"
Using one of four different factors (completely ignoring S3, which in and of itself isn't exactly fair) to compare pricing is making a claim that isn't supported by the evidence. If you provided a typical actual breakdown of storage costs versus access costs, and then used the total differences in price structure to arrive at a comparison price, then could make a claim about the comparison between the pricing for both services that was actually based on facts.
How does one multiply to get less? 10 times 1 is 10. So, what exactly is "10 times 1 less"? Is it like a negative exponent? 1 to the -10 power? That would be less, but I've never heard anyone say "times" in reference to an exponent.
