The highly anticipated voice-search enabled version of the Google Mobile App for the iPhone appeared in Apple's iTunes Store on Monday evening.

"The new Google Mobile App for iPhone makes it possible for you to do a Google Web search using only your voice," explains Google mobile engineering manager Dave Burke in a blog post. "Just hold the phone to your ear, wait for the beep, and say what you're looking for. That's it. Just talk."

There's a bit more to it than that, but mostly the new Google Mobile App is fantastic.

It took a few tries to get the timing right. The app senses when you move the phone to your ear to begin recording. On my first few attempts, I spoke my query before the phone was in place.

Thus my query "French restaurant" was interpreted "Toronto," because the phone only caught the tail end of what I'd said.

But once I was more patient and waited to hear the tone before speaking, Google Mobile App proved to be remarkably good at understanding what I said.

I tried speaking with a regional accent to gauge the app's flexibility. A Tony-award winning moment it was not, but it seemed a worthwhile test. My attempt at Southern-inflected English, "eye-talian food," to my surprise returned results for "Italian food." But mimicking my father-in-law's Baltimore accent, "fried ayggs" instead of "fried eggs," was interpreted as "Fridays." So TV newscaster diction is recommended.

I tried "pizza" and Google interpreted the word correctly, returning a list relevant search results. There was a link to Pizza Hut at the top of the search results list, followed by three local San Francisco listings for places to get pizza. When I tried this search on Monday evening, Google served an odd ad: The top sponsored listing was for a site called RapidScreenings.com that advertised STD testing. But on Tuesday, that glitch had been fixed: A Domino's ad appeared in the sponsored results. I asked Google to find a "hardware store," "French restaurant," and "Starbucks." In each instance, it interpreted the words correctly and returned relevant search results with links to local places.

I tried "Where can I get a good cup of coffee?" and Google transcribed it accurately. But that search didn't pull up any local listings.

I tried "define ambiguity" and Google accurately interpreted my query and responded with a definition, just as if I had typed the word into the search box.

With the query, "show me my location," Google returned sponsored listings for Google Maps and Mapquest, and a link to ShowMyIP.com at the top of the organic search results list.

The bottom line is that Google Mobile App does a remarkably good job of understanding spoken words, which makes it extremely useful for situations where you want to search without typing on the iPhone's touch screen.

One area where Google still needs to do a bit of work is with names. Because names that sound the same can be spelled many different ways, Google Mobile App isn't great at searching for people.

If you say a famous name, like "Barack Obama," Google identifies the name properly and returns good results. But taking my surname as an example, "Claburn," Google returns "Claiborne," which is phonetically correct but doesn't return relevant results for my purposes. Google provides a drop-down list of alternatives in the search bar, like "cleaveland" and "cleburne," but again that's not the spelling I meant. Score one for typing.

This isn't a major issue since Google is aiming to provide voice-driven local search, but as social networks and personal location data become more intertwined, asking Google to find your nearby friends could become more common. Google will probably be able to solve this by running through address books and social networking friend lists. Doubtless there are privacy issues to be worked out.

Until that happens, there are always iPhone applications like Loopt.