Entire sites built in Flash are ok in the following situations:

• You have a budget to burn on a team of designers and programmers
• You design really cool interactive games and applications built in Flash
• Your target market is one with higher end computers and they don’t mind having to install software to view your site
• Users in your target market typically have high-speed internet connections
• You have an alternate mobile-accessible or Flash-less site.

Flash is ok if:

• It is used sparingly to create effects or interactivity
• In those little ads on MySpace
• It doesn’t contain all the content of your site

Here is why: People want straight-forward sites.  They don’t want to wait for ages while your site downloads.  I have a high speed internet connection and I hate waiting through the spinners and page load animations to get to a site.  But they can be super totally awesome.

My point is if you are out shopping for a car, you wouldn’t get the one with all the bells and whistles just because you could afford it.  You would research it, see what is going to give you the best value.  That new Ford has nearly as many features as that Mercedes but the cost to purchase and maintain are much lower.  But I do know that sometimes you just have to have that Mercedes.  Just like sometimes you just have to have your Flash.  But use it smartly, and you will be rewarded.