The disadvantage of flash is that it can't be indexed today or in the near future. DON'T hire a design that wants to build you a flash site or sell you a template that he downloaded for $25 from the web.
If you want search engines to find you DON'T use flash. Flash is an incredible tool but it just a tool and should be use in appropriate places. Some designers will tell you that they add comments and that's good enough... WRONG. Search is very intelligent, using linking to you, depth of linking, and the quality of the sites linking to you.
If you have a flash website then all your links, all your content, your footprint on the Internet is the one page that the browser loads when you first hit the website.
Intros... I thought this was over years ago.. stop having intros. I mean really, if you want to show them a commercial then ask them on the landing page but its like you are forcing them to watch a commercial when most of us spend hard earned money to avoid them "TIVO"..
This has been my rant for the day