(CNET) — Microsoft’s Bing took a major step forward Wednesday in adding rich mapping and image data to its search engine, but until it assembles more data, pretty pictures aren’t enough to beat the Google Maps juggernaut.

Bing Maps Beta was released during a presentation at Microsoft’s offices here. It’s a Silverlight-based application that runs inside Bing Maps and adds Microsoft’s version of Google Street View — called Streetside — to Bing Maps, as well as enhanced “bird’s eye” images that let you swoop over cities.

I spent some quality time Wednesday afternoon with the new Bing Maps Beta, zooming through the streets of San Francisco and New York and testing out various searches.

The best part about Bing Maps Beta — by far — are the rich transitions between high-resolution street-level or bird’s-eye view photos as you move around a city, making it feel like you’re actually driving down the road.

Unfortunately, that’s also the worst part; you’ll have to download Microsoft Silverlight to make the rich imagery come alive (although you can still use Bing Maps without it), and 10 minutes of poking around with the application put a noticeable drain on system resources.

If I left the window open, but didn’t do anything in Bing Maps, my activity monitor dropped back to a moderate pace, only to max out again once I started playing with the Streetside feature or scrolling around a map.

But what Microsoft has assembled is impressive. The images are high-quality, and the location fixes are quite precise. The bird’s-eye views have been improved with more perspective on roads hidden by buildings and name prominent buildings right on the map.

Scrolling around a city in bird’s-eye view also allows you to view geotagged picture galleries created with Microsoft Photosynth. Click the little blue Streetside man (Google’s little Street View man is orange) to choose between Streetside or Photosynth views, and if you click on a green icon in a given location, you are presented with photo galleries shot of the location.

You can check out exhibits in museums such as New York’s Metropolitan Museum of Art, for example, zooming into the building from the bird’s-eye view.

Microsoft is launching Bing Maps Beta with Streetside coverage of about 100 metropolitan areas in the U.S., but it’s really only useful for traveling or searching medium-size cities or larger; suburban data is quite light.

And even within cities such as San Francisco, Streetside is limited to essentially the downtown areas. Microsoft representatives said Wednesday they plan to add more data as soon as possible, but it could take quite a while.

A more generic search for a city or town such as San Francisco within Bing Maps Beta brings up a Wikipedia article on the city, weather information, and links to Photosynth galleries on the left hand side of the page alongside a map of the area.

Clicking on “more details” brings up links to more photos, local news and “popular landmarks,” although Microsoft should probably rethink the listing of the Port of Oakland as a popular San Francisco landmark.

Search for a specific address, such as CNET’s downtown San Francisco office on 2nd Street, and Bing Maps Beta provides helpful icons to bars, restaurants, gas stations, and other locations within a given radius when you click on the “What’s Nearby” icon.

It’s pretty easy to get directions between two given locations, such as Microsoft Research’s Mountain View, Calif., labs and CNET’s downtown San Francisco headquarters.

Bing lacks Google Maps’ nice addition of Street View photos of each turn — since it doesn’t have nearly that much data — but makes up a little bit of the gap with a helpful “if you reach X street, you’ve gone too far” reminder at the end of the journey and also listing prominent landmarks at certain turns.

Microsoft has an awfully long way to go before it can duplicate the reams of Street View data that Google has assembled, as seen with its directions feature.

Its rival certainly noticed Microsoft’s announcement Wednesday, putting out a blog post of its own highlighting the fact that it has added Street View images of Sea World and second-rate New England learning institution Boston University.

At the moment, Google Maps has Bing beat when it comes to speed and comprehensive data. In addition, Google also surfaces some of the same helpful data, such as photo galleries and even videos.

Bing, however, offers a much richer look at the world. It does this at the expense of performance, but it presents a credible alternative to Google Maps for travelers and residents of major cities.