Relevant keywords in Google Webmaster Tools

Dear Friends:

First, I've to request apologizes about my bad English. I hope you understand my questions.

I'm a new user of vbulletin and vbseo. I migrated my forum from phpbb to vbulletin a month ago and I have a question about the "key words" section in the google webmasters tools.

My forum is about horses, and all the related sports (classical dressage, showjumping, and more). The list of keyword for google are, in this order:

1.- horses (I think that this is good)
2.- messages, message
3.- forum
4.- users, user
5.- joined at
6.- reputation
7.- share
8.- vbulletin
9.- linkback
.....

The only keyword related with the main theme of my forum is "horses". All the others keywords are words that are commonly repetead in the forum, but they are not keywords related with my forum.

Now, I want to ask, if this has some relevance for google or not. And in second place, how can this be improved?

For example, the word "message", is repeated hundred of times in the "showposts" pages. Users can not see this word, but in the html code, in many links title tag, for example, "go to last unread message", "private message".

Any ideas?

Thanks in advance.

R. Campos.

Please see:
Google Sitemap Keyword Relevance - vBulletin SEO Forums