That $100 million advertising budget for Bing appears to be worth every penny. A recent study from comScore, Inc. shows just how well Microsoft's new search engine has done in its second week of business.

Bing's daily penetration among U.S. Search engine users has raised 3 points, up to 16.7%. Its share of search result pages is also up 3 points, to 12.1%. It's undeniable that Bing is growing. These numbers show that people are continuing to flock to the young search engine and that, so far, the early adopters they've gained are sticking with Bing.

Of course, Bing hasn't even been out a month yet. These numbers are great for Microsoft to brag about, but they really mean very little at this point. If Bing is showing growth in 3 months, I'll be impressed. If they're holding onto a substantial portion of the market in a year, I'll be prepared to call Bing a success.

The thing to remember here is that Microsoft is still throwing bales and bales of money at Bing. They can't keep up this level of advertising forever. Bing is operating at a loss right now, there is no way its revenues are keeping pace with the cost of the ad campaign. Once Microsoft stops pumping money into ads, we'll see just how much of a user base they've actually managed to accumulate. Until then, Microsoft's got nothing to brag about.