I found (sorry if I overlooked something), that the positioning of thumbnail images is not yet perfectly solved, see for example http://meta.wikimedia.org/wiki/Sandbox/Thumbs and its wiki source code; it is probably related to a not correctly interpreted or coded css.
The text of many contributors under "Layout of tables, images" on page http://meta.wikimedia.org/wiki/MediaWiki_1.3_comments_and_bug_reports was of no help: the problem of misaligned pictures appears to be independent from the presence of categorie links on that page.
Main question: How can one position a thumb image left or center or right aligned (appears to be the default) ? It's not possible for me, I am using Netscape 7.1; the same effect under InternetExplorer 5.5 and 6.0, Classic Skin.
Could someone of the developers please check and perhaps solve this problem in a next version. The thumbnail function is a very powerful tool of MW - thanks for inventing it.
Tom
wikitech-l@lists.wikimedia.org