Well the Index is a made up index of 100 stocks. There is two indexes the VMI which stays the same throughout the year with no rebalancing, and the VMIR which rebalances monthly at the end of every month.
The Index is meant to be a microcosm of the board ideas http://investorshub.advfn.com/boards/board.aspx?board_id=3251
The Index was created for several reason, about 5 years ago we often found that our stocks wouldn't always move in the same direction as mr. market we had nothing to compare our individual performances too, so an index of 100 stocks was created, then several months later the rebalance idea was brought up, and that is where this index is today.
To read up more on the Index, I suggest you read the I-box, as there is some stuff on Methodology. It shows what went in and out every month so far this year. Historical Returns, etc.
I want to say these stocks are risky, just look at 2008 performance of the index, then again everyone's 2008 performance wasn't very good. But as I said before these stocks are very risky, and are not for everyone, because it can often be a roller coaster ride lots of highs and some really bad lows, but overall the indexes has done quite well since being created. Not that I would suggest to anyone to buy 100 stocks as that in my opinion is waaaaaaaaaaaaay too much diversification, but everyone idea of diversification is different, mine when I'm fully invested is about 25-40 stocks. Then again what the heck do I know? All above is just my opinion, and I could always be wrong though.