The popular 3rd party Android web browser, Dolphin, was ported by the Handster team earlier this month. I did not have a chance to try it when it came out but now that everybody is upgrading to PlayBook you might want to check it out. I find that it is a great alternative browser to the native PlayBook browser. It lets you do things like change your useragent that you cannot do on the PlayBook browser. On the other hand it is buggier and relatively slower though it does have some cool gesture based navigation.
Check out Dolphin browser HD for free in App World. Keep in mind you may see a white screen at launch if its the first time you have launched a Android Player app. Also make sure to rotate it to landscape after you go through the simple setup that only works in portrait.