imo the bubble is one of the most important stages of a MTT.
If you got a big stack, you can use it to bully the other people at your table because they want to cash at least. It's important that they got significantly smaller stacks than you, or that the bigstacks folded their hand already. You can easily steal a lot of chips during the bubble period with a big stack.
If you are the smallstack you should look for a good spot to double up or steal the blinds. Only move here is all-in because otherwise you will give the big/middlestacks good odds
to call. With around 10BB's you are potcomitted directly, so you cannot fold anymore on the flop. When you move all-in you got "fold-equity", that means your opponent will fold a lot of hands and you will collect the blinds.
As you see its better if you got a big stack (of course.. ). Also because MTT's payouts are very top-heavy you should NOT play for a "in the money finish". So you need to take some risks before the bubble to be a big stack and not one of the smaller ones when the bubble is there..
just my 2 cents..