Unless you have a Windows Phone 7 or access to marketplace from Zune, you cannot browse the Windows phone 7 apps available. MarketPlace Browser is a nice useful website which has all the Windows Phone 7 apps listed and you can browse them based on various categories. In case you want to download or buy any of the apps listed in the market place, the site provides you with link to Zune to download or buy.
One thing good about this site is the way the apps are listed based on the categories, makes it easy to find an app. There is also a search to find any app from the complete list. Currently the browser has almost 2436 apps listed, hoping that the author updates the new apps added.
If you are looking for another Windows Phone 7 market place browser, check this out.
