Awesome script and really cool idea!
However, I cant get it working :/

I tried via tampermonkey and greasemonkey as well as through the console in chrome and firefox.

No link gets created, but maybe its just me being too dumb.
When using the cmd line in the console in chrome, I get the following error:

undefined
Uncaught TypeError: Cannot read property 'toUpperCase' of undefined VM7065:2

In firefox I get:
undefined
TypeError: O is undefined


Another side note: Any chance you could include cheaptickets.com as well? Cheaptickets has exactly the same url structure as orbitz but most of the time it prices it a bit cheaper than orbitz and also gives better results when including many tricked routes, thanks!