Many software companies preach in their Website Banners: "Global Delivery Model". Has it anything to do with Deployment?
"Global Delivery Model" has nothing to do with software "Deployment".
The term Global Delivery Model is typically associated with companies engaged in IT consulting and services delivery business and using a model of executing a technology project using a team that is distributed globally.
Actually this is a marketing term is used by software services companies(mostly offshore companies) who have their team distributed globally to provide 24/7 support, less cost etc to attract clients when bidding on a project.
more details @ http://en.wikipedia.org/wiki/Global_delivery_model
Global Delivery Model usually implies one of two things:
1) Uses cheaper resources from overseas.
2) These resources can work around the clock, so you can finish a day of development in one region, and have it tested overnight in another.
To answer your question, I find it only nominally about deployment. (I like the answer @java_mouse gives, though I'm not quite as extreme) An organization that is located around the globe can provide deployment support 24X7, and can help provide resources close to your customers if you need. But this is ancillary to points 1 & 2.