Sony's latest firmware version for PS3 (v2.5) nows provides support for proper 50i playback of HDV footage, not the 50/60i conversion which was previously employed which caused motion judder:
Settings
* [BD/DVD Settings] has been renamed as [Video Settings].
* Under [Video Settings], the [Cinema Conversion] and [Upscale] options have been renamed as [BD/DVD Cinema Conversion] and [BD/DVD Upscaler], respectively.
* [Sequential Playback] and [50 Hz Video Output] have been added as options under [Video Settings].
Official PlayStation website: System Software- Update features (ver 2.50)