If you're only coming for 2 years, you need to make a bet on the US real estate market. Depending where you are in the LA area, your area might be protected more from a downturn than other areas. If you have a friend in real estate, you might talk to them to get more info. Some people see a significant downturn coming in the US property market (in fact, it's already there in many places). How much and how long are the unknowns obviously.
If you have some friends who can rent your place and give you enough to cover your mortgage and property taxes, then this is probably the way to go if your employer is guaranteeing that you'll return to LA. Giving them a break on rent to do normal maintenance, etc. can work out well for both sides, too.
If there's a greater than 50% chance that you'll not return to LA or not return withing 2-3 years, I would look into selling provided you won't take a hit on the sale. We held on to our house in the US for about 4 years or so after moving here. Granted it was an older house and we didn't know our renters so it wasn't cared for in the way it needed to be, but we found it was too much of a hassle to deal with from Switzerland.
It's a good idea to keep a US mailing address and keep 1 credit card at that address (we use a family member's address). Some websites only take credit cards with US addresses so this helps. Most likely, you can sign up for statements by email so you won't need to worry about your friends charging a new LCD TV on your credit card.
If this remains your current home with your friends forwarding mail, then this could be a nice service. However, you'll want to have most of your bills/subscriptions changed to your Swiss address rather than having them forwarded since the cost will get to be too much.
One tip re magazine subscriptions...extend them at US rates while you're still there. Most companies will honor the original subscription period after you move rather than charging you a higher international rate.
As for renting in Switzerland,
www.homegate.ch is very good, at least in the Zurich area. I understand it's pretty comprehensive for the whole country, too. Make sure you click the English link. House/flat sizes will be given in square meters (about 10.5 sq ft to 1 sq mt).