Ok, a little polishing point here.
The email template for the group invitation text is set up; as follows.
<pre><InvitationText></pre>
As I am sure you are all aware, (well, most of you anyway) the <pre> tag is short for preformatted. That means whatever spacing and carriage returns exist in the text you place in the editor box for the group invitation will be maintained when it is delivered to the email.
The box is too small. If you type the text in, you end up with text that looks like:
now is the time
for all good men
to come to the
aid of their country
In other words, the person manually typing the text into the box is limited by it's design and won't know his or her text will appear like this in the outgoing invitation email. If they cut n paste a block of text into the editor, then they risk no word wrap at all and the person receiving the email will have to scroll from side to side to read the entire message.
Now, it does work as intended and if you use an editor, you can make the paragraphs and line lengths exactly as you wish and it will apepar in the email that way.
But who is going to do that outside of the site administrator who may or may not be aware of the problem?
I would say if you want to contain the message in <pre> tags, then the editor box you provide should be the size (width wise) of the average email viewing pane. That way, at least the person sending the invite has a 50/50 chance of sending an email that doesn't look like a child created it.