Comment 10 for bug 147819

Concerning the default of preview: I'm rather sure, that ooo-preview is not a default, even not for gutsy, but I may be wrong.

Concerning the Documents and screenshots you've posted: please re-read my comments, especially the last part of comment #4:
> the background of the preview-image is transparent, on dark surfaces with white, on light surfaces with black text.

So your screenshots are showing exactly that behavior.

Again: The preview of ooo-files is not a (nautilus or thumbnailer)-generated preview of the given file, it is the extracted content of the preview image embedded in every opendocument file.