Similar pages - style wise

Google recently listed 1 page from my site then said below it had omitted a page which was similar to the other.

I found this rather strange as the page although similer in a way (style - ie little articles (50 words) and a pic seperated by <hr>)the page offers completely different information. Some of the links in the side bar are the same.

However when I looked I noticed I had use the same page description for both pages. Could this be the cause of google ommiting it in a search? I have since change the description and page title

It has now frustratingly dissapeared from google as has every other page they have listed over the past 2 months. They seem to appear for a day or a week then go again. I realise this is probably my fault but if googlebot was a man id like to poke him in the eys with a stick.