I don't know how popular or usable is a Panorama photo, but it's definitely a way to spice up your portfolio and allow prospect buyers to view new and different angles of popular sites.

The good news is, they are really easy to photograph and create.
When you want to shoot a Panorama, the most important thing to remember is the exposure values, i.e. if the lighting conditions varies from frame to frame, you will get an uneven exposure that will be marked by diagonal lines where the images are overlapping.
The best way (if you use an SLR or Advanced P&P) to deal with exposure fluctuation, is to use exposure lock. I usually measure the brightest point in the frame and lock the exposure. it may shadow darker places, but will give an even look for your photo.
Another option, is shooting in a overcast day, but these days are pretty rare in Israel, and if you read my previous posts, you know that I shot when I can, but for the pros among us, it's a good place to start.

Here is an example of evenly exposed photo with partly cloudy skies. the exposure made from the light areas, allowed for the dotting of the terrain in dark and light patches and created a nice contrast to the end of summer colors of the area.


The actual shooting of a panorama is quite simple too. After you figured out exposure, start shooting from one side to the other, allow for about 30-40% overlapping between each frame, and look for bold marks as a reference point to your movement.
To sum up, panoramas, once the possession of pro level photographers and extremely expensive cameras, is now an easy and exciting way of adding value to your portfolio, and giving prospect buyers another perspective on popular sites.
Amitai