A lot of domains now seem to prefix their domain with ‘get’, for example getfirefox.com. How do people view this from SEO perspective as opposed to just firefox.com?
From an SEO perspective, this should not affect your business in any way. A lot of these new businesses prefix their brand name with ‘get’, ‘try’, etc. since the original brand name is not available. The only problem I see with it is that when you start getting brand recognition, people tend to go to the original brand name. For instance, if you own getfirefox.com and Firefox is your brand, people tend to try and visit firefox.com by default. You could lose customers in that case.
Would it help to use postfixes? eg firefoxapp.com?
Domains availability or lack the of has a lot to do with it. But using a verb to prefix a domain is like giving the customer a call to action and reminder at the same time. Esp with a good play of words w/ your online & offline marketing material.