Web pages and video for smartphones

After a Quick look at the Blackberry 8700g Smartphone, I found there are very similar looking rival units, such as the Motorola Moto Q, Nokia E61 and Sony Ericsson M600i. While I have written about how to do web pages on such units, I have had a few queries from people about video for training purposes for them. I am not sure that is really a good idea and audio with slides might be better with MMS (SMIL for mobile phones). Video might work better on larger devices, such as the Microsoft Ultra-Mobile PCs, and games units, such as the GP2X with Linux. Anyone had any experience?