My story comparing results from Google and Wolfram Alpha met with considerable curiosity from about 250 commenters on Slashdot, as well as more on this site.

Some critiqued my approach, others wondered what would've happened if the queries had been worded differently, and others posed hypothetical searches of their own. I'll try to answer these questions and comments in this post.

In my story, I described searching for "Cancer New York." Wolfram interpreted this as a hunt for the constellation, and it gave me astronomy information. Google gave me links to cancer centers and a state cancer registry, which seemed about right.

But one Slashdot commenter called "chill" fired back, "Nobody knows what the hell you mean with 'Cancer New York' because there is no context. How about 'cancer statistics for new york' or 'cancer treatment in new york'?" Another commenter made a similar point, adding, "All his other searches are equally stupid." So I went back and tried "What are the rates of cancer in new york," "Cancer rate in new york," and a few other variations in that spirit. In each case, Wolfram Alpha came back saying it "isn't sure what to do with your input."

Another commenter, "lymond01," wondered if Wolfram Alpha knew Demi Moore's age (as Google does) and whether it would point a searcher to the primary source. Wolfram did fine, giving her age as 46 years, 5 months, and 25 days. However, while it listed several sources, it wasn't clear from which source it drew the answer. So if I had been writing a news story, I would have been left high and dry--not wanting to quote a search engine, and not able to quickly discern the primary source. That same commenter wanted to know if Wolfram could answer the question "How many French died at the Battle of Agincourt?" I tried; it couldn't.

Finally, this commenter added, "Eventually, this will all boil down to me driving in my car and saying, 'Computer. Tell me: At what speed did Marty McFly need to drive to travel in time?'" So I actually went and tried this, and a few other variations. Wolfram didn't know anything about Marty McFly (the protagonist of the film Back to the Future), but when I tried "flux capacitor" (the gadget in the film that powers the time machine), Wolfram interpreted my question as "power required to operate the flux capacitor in the DeLorean DMC-12 time machine" and gave the correct answer: 1.2 gigawatts, which it further elaborated was one-tenth the power of the Space Shuttle at launch.

"Atomicjake" wanted to know how Wolfram would do with the following searches: "How many bull terriers are in the UK," "How many blind people live in the US," "What is the color of a strawberry," and "strawberry blackberry." Wolfram was unable to answer any of the first three. On "strawberry blackberry," it gave me a nutrition label listing the nutrition information for 140 grams of strawberries and 144 grams (one cup) of blackberries. Note that it gave the combined nutrition information.

Critiquing my search for "10 pounds kilograms" and my complaint that Wolfram Alpha interpreted this as an effort to multiply 10 pounds times 1 kilogram, "maxwell demon" remarked, "WA's interpretation is the most reasonable. After all, it's the standard way to denote multiplications (as in newton meters, ampere seconds or kilowatt hours). It would never have occurred to me to omit the 'in' even in Google." I hadn't thought of this. I suppose that's the reason why Wolfram interpreted my input as it did. But that didn't make Wolfram's answer any more helpful. Surely anyone searching for "inch centimeter" or "minute day" most likely wants to know how many centimeters are in an inch or how many minutes make up a day.

Here on our site, a commentator who signed his comment "Nate" wanted me to run the following queries. I did, and the results are in parentheses.

What is the cheetah's top speed? (Alpha didn't know--but it offered me a page with lots of cheetah data, which didn't include speed.)

Are any two snowflakes alike? (Got nothing.)

What is the genetic sequence of the common fruit fly? (Stumped. I tried the question with "drosophila," but that didn't help any. A search for just "drosophila" gave me a definition.)

Where can I see The Soloist in Milwaukee? (Nope.)

How many copies of Harry Potter have been sold? (Nope. The Wolfram people have told me that popular-culture data will come later. And the version I have access to is not the latest one.)

What are the 100 biggest companies in the world? (Nothing, although when I tried "biggest companies," it interpreted it as "biggest financial"--but then the computation timed out and it quit.)

How much larger than earth is jupiter? (This one it did fine. It asked me if I meant "Jupiter, the Earth" and then gave me tables with tons of comparative data, including the answer to that question.)

How far away is the sun? (Yes, it did fine--tons of data, including distance.)

How many solar systems are in the Milky Way? (It didn't give me an answer.)

Another Technology Review commenter wanted me to ask, "What is the population growth in France between 1980 and 2000?" (The answer was quick: 0.419 percent; it said this was a 2005 estimate and gave sources.) When I asked for the population in each of those years, as the commenter suggested, I got the numbers, charts showing the increase in population over time, and other data.

Going back to Slashdot, commenter "harlows monkeys" said, "You can't meaningfully compare Google and WolframAlpha, because what they are meant to do is so different." I disagree: while it's true that Google primarily searches the Web, and Wolfram Alpha primarily culls and calculates answers from databases, they are both meant to answer your questions usefully. And they don't have mutually exclusive approaches. Google readily and usefully computes answers on common questions such as metric conversions--and it recently launched a feature that culls information from public databases, starting with census and labor data. And Wolfram isn't only coughing up numbers: it also gives you written definitions, and Wikipedia links and source links. And it's definitely meaningful to make direct comparisons in instances where you are seeking a piece of data or a calculated answer.

A commenter named "Jugalator" slammed the article thusly: "Stupid 'face off' story. WA doesn't compete with Google." That's what I thought--until Google decided to make its announcement of its own data-centric service during the very hour that Stephen Wolfram was giving his demo at Harvard last week. If that wasn't a competitive jab, it was at least a lunge for turf in an expanding search frontier.