I am against putting:

Tweeters
- or -
Tweeters -

in the subject line of messages. This breaks sorting by subject line as
every subject line would start with the word "Tweeters".

However...

[tweeters]

in the subject line would be OK. Most email clients will treat words in
brackets [] just as they do "re:" and "fw:" so sorting by subject still
works correctly.

I question the need to add a prefix to the subject line as most email
clients have the ability to filter messages based on header information (To:
and From: fields) as well as words in the subject and body of the message.

The only real need I currently see for adding a prefix to the subject line
is if there are people subscribed to Tweeters who's sole means to read email
is via a web client (HTTP Mail). I know of few HTTP Mail sites that offer
mail filtering and those that do the filtering options are few.

Bruce McKenzie
Kenmore, WA USA
mailto:bmsh.mckenzie at gte.net