The first thing you should do is talk with your Realtor; you might be surprised at where the market is and what your home is worth today. Values have increased and are equity is growing in many of our Oakland homes.
If you are thinking about doing a short sale you will need to figure out if you will be approved for one first. In order to do a short sale you must have a hardship- examples would be job loss, reduction in hours or pay, medical reasons, divorce etc.
The rental market is pretty hot and it might be an option to rent out your place and have the rent cover your cost or at least most of your cost.
Sit down with an Oakland agent and discuss all your options.