"When it's done"
The guys doing the work on the driver have no blue prints to work from, they basically create an NTFS partition, look at it, change something in NT, see what changed and try to figure out what all happened. The read drivers for 2.5 are said to be a lot faster and cleaner than before and are considered done, writing research has just begun. If MS would stop changing it a little with every other release of NT it would be easier, but then again that's why they do it.
Basically don't hold your breath, it'll always be a work in progress.
If you want it done quicker, bitch at MS for not documenting the filesystem format publically.