Maybe it is time to write down some guidelines that you should keep in mind while working with SharePoint 2007, or you could just ignore them as well. I found these guidelines in Blogs, articles on the internet but I wanted to group them together. 
  
       |  | Limit  | 
  | # site collections in a web application  | 50.000  | 
  | # sites in a site collection | 250.000  | 
  | # subsites nested in a site  | 2000  | 
  | # lists  | 2000  | 
  | # items in a list  | 10.000.000  | 
  | # documents in library  | 2.000.000 | 
  | # documents in folder | 2000 | 
  | # documents in index | 50.000.000 | 
  | Maximum document file size | 2 GB | 
  | # search scopes | 1000 | 
  | # user profiles | 5.000.000 | 
   
 These guidelines are not hard limits, meaning if you have 2005 lists on a site, your site will still work. The only thing that could happen by adding more items is that your performance could decrease.