adding to users table?

Hi, I have a quick question about adding to the liveuser_users table;  
seems like I remember one of the examples doing this.  I would like to 
add FirstName, LastName, etc., and avoid having to cross-reference 
another table of my own making...is there any reason I should avoid this?

thanks,
-stacy

-- 
Stacy Johnson
[email protected]
206-354-5591