Plugins: File attributes via DOpus plugin or IColumnProvider/SysProps

I want to have some information about a specific file-type (torrent files) available in the tooltip just as with image files. Information may include things like number of files/directories, total torrent data size, etc.

I studied the DOpus plugin support, but it seems that this can only be done for specific attributes of audio and video files.

Now I see that the TortioseSVN implements this with the IColumnProvider interface. Although this interface is not supported under Windows Vista anymore and System properties have to be implemented for that.

So my question is: Is the only way to implement a Windows XP and Windows Vista compatible solution is to implement both IColumnProvider and System properties?

Greetz,
ommos

I think you can just use IColumnProvider. Even though Explorer on Vista dropped support for that, for some inexplicable* reason, I believe Opus still supports it even on Vista, so anything which registers itself as an IColumnProvider will still work in Opus. Tortoise certainly does.

(*Or perhaps not that inexplicable, given the many other insane changes and design decisions made to Explorer in Vista! I think I'd hate Vista, instead of quite liking it, if I didn't use Opus.)

[2015: These days you could do this using a fairly simple script.]