No one can tell you what the market will be like at any time in the future. The real estate field is inundated with pundits and prognosticators that are about as right as the wheather men. Even our own cheif economist at the California Association of Realtors will point out how far off she is every year on her predictions from the past year.
To sell your condo you will need about 10% of the sale price to cover transfer taxes and fees. The very good news is that you bought in one of the best neighborhoods in the best city, so even if you need to hold it for a while you should do OK.
I would suspect there will be a some appreciation but it will not be in double digits. 2008 is projected to be a slow year with the market getting better towards the end. Property appreciated last year around 3-4% but the number of properties sold dropped about 13-15% depending on where you get the figures. It really depends on the economy, interest rates and what happens with a new President. No one can truly predict -- it is just a guesstimate on everyone's part.
I think you will be fine if you pay your mortgage on time. The subprime debacle is not as bad in San Francisco, at least in the North end of town where you live. Hang on to your property - it is always a wise investment in the long run.
I wish I had a crystal ball! I usually advise clients to hold a property at least 3 years to recoup their selling costs. Overall the economic predictions I've read say that San Francisco should be fairly even over the next couple of years, although with minimal appreciation from 1% to 4%, and good job creation. You can take a look at data quick's numbers and I think they have some predictions on markets on their site.