Nokia don't use IVA or No IVA?
If Nokia don't use it ,that will mean:
maybe Nokia will turn on it in the future or by the third party software.
If no IVA in N800's processor,that's a bad news.

I have tried play many .rmvb files,but it is not very smooth,but when I reencoded them to mped4,they will be better.Decoding the rmvb files consume too much CPU resource.