Bob, if you don't buy my counter-argumet, take a newspaper. Cut it in columns and glue the end of each column to the beginning of the next one. Try to read the obtained scroll :))). You'd instantly wish the columns were a bit wider.
The argument holds until somebody makes a multi-column display in a browser to utilize the screen area better (somewhat like two-page print preview in Netscape), which is not going happen soon.
The list of allowed tags is evil. It is not security, it is harassment! Have you ever had a problem on this forum? Then turn it off please!
There are many small communities where such abuse by insiders is of question and abuse by outsiders won't be a danger too because of little public interest to the community. I think, photo.net grew larger than most of existing (Open)ACS communities before they ever had an accident with tag abuse. It's good to have this security tool in place, but it need not be switched on by default and need not be so restrictive. It prevents useful content from being posted (e.g. images, tables, and whatever else you inevitably forget to specify in the list of allowed tags).
If you make a filter, there should be also an option to specify tags which are NOT allowed, passing everything else.