I like Street View a lot, but the interface is really clumsy, so I was delighted to see something that makes it more useful. This is an improvement, particularly if you're lucky enough to land on a good shot, but it's still clumsy. I'm sure they'll work at the bugs.
The left side interface is too busy. Some links in the left-hand column will give you the street view option, and some won't. Eg, if you're familiar with map results, you'll know not to click "more info" if you want Street View.
The information flag is going to block your view every time. Sometimes the view is pointing down the center line of the road... sometimes it's pointing at the address you want. Trying to drag the avatar along the street on the map is going to make you wish you'd never tried.
I was pleased to see that there was a video ("Finding a business with Street View (short)") on the LatLong blog page to show you how Street View works, because several maps interface features, particularly Street View, are crying out for video help.
Unfortunately, this video was not helpful. It had no audio track. It had little caption boxes instead of narration, with the caption in one part of the screen and the cursor you were watching in another.
To be generous, I'd call it a work in progress. They desperately need some good interface design.