The stock market surged last week on better economic news. However, bonds didn't do so well.
Unfortunately, there is not much economic news coming out this week that will effect much change.
Ben Bernanke testfies with the House Budget Commitee late Wednesday. He is only expected to speak about employment, U S dollar and the nation's debt ceiling. I'm not sure if this will have any effect on rates, as housing isn't likely to be discussed. However, since the trend is upward, I would not wait to lock in a rate.
There are still worries about Egypt and the effect their revolution will have on other Middle Eastern nations. Things have been mostly peaceful in Egypt since last Friday. However, this could change as well. Instibility there would probably bring rates down.
Again, the trend hasn't been downward. I would say to lock in, as of now.