We have some very interesting projects that integrate Google Maps with panoramic images. They can also be combined into full virtual tours.
We have created Virtual Tours and information sites including one project for the Marine Discovery Centre Virtual Tour that also includes interactive Google Maps and our Content Management System. (this news and video system is part of our CMS)
It includes original sound tracks including panoramics for each location.
One area is VR and panoramic images - perfect for a real-estate site.
This is a cost effective way to display panoramas without the high cost of a professional photographer. Click the video icon to see the example shot 200 metres from my office at Main Beach (another good reason to update your site). Use your mouse to guide the panorama. This is shot using a good quality tripod and a Nikon SLR digital camera.