Ofir has written a very detailed blog post about the new HTML component in LWUIT which you should probably check directly from him. He also wrote a very cool application making use of this component to browse parties in the MWC event! You can see a video of this application in action on the right side.
The HTML component in LWUIT is one of the most sought out features in LWUIT since day one. It required tremendous amount of work from Ofir which is still ongoing and the component still has allot of work pending. However, we do want something to be 100% clear: this is not, nor will it ever be a "browser in LWUIT". Opera, Bolt and other mobile browsers are usually implemented either with a native component or with a server component. The LWUIT HTML component is designed for very specific use cases that don't necessarily require a server component. So keep your expectations in place and don't expect the HTML component to render everything you throw at it since it isn't designed with that purpose in mind.
The HTML component is an example of a trend we have for quite some time of building composite components, that is assembling a component from multiple simpler components rather than implementing a component using graphics.