Originally Posted by DWB

A lot of people are stuck in their ways and habits or just follow what everyone else has been doing. MP4 is superior. FLV is not needed. You can offer a few different MP4 sizes. If you use a streaming server, it can pull the correct size based on the users BW. Also, with MP4, you can really pinch them down and still have great quality, so you don't need as many versions. Some people still like WMV, I don't know why. We still offer them (1 wmv) in addition to our MP4 because webmasters (and review sites) are not video educated enough to know you don't need them and think your site is bad if you don't have them, yet MP4 plays on PC and MAC and is better quality at a smaller file size.

You will find apple devices will need a fall back html5 player to play your mp4, but that fall back comes built in now to the new players.