I am running 10.3.1 on a Pismo. Safari is updated, but I noted that the program would sometimes just sit and not load the page I wanted. In fact, according to the packets sent and received - it showed zero. Sometimes the page would timeout (ie "server cannot be found") error sometime the page would finally load after 15-20 secs. I have a cable connection.
For reasons unknown, by clearing the safari cache the page would begin to load. Weird. It got to a point where I would clear the cache almost every hour (depending how much surfing I did).
I read on the apple discussions that the "freezing 10.3.x" may be due to the crashreporter. I too had the "freeze" a couple days ago, but I rebooted and it hasn't come up again. nevertheless, I killed the "crashreporter" process. Surprisingly, Safari is performing flawlessly, and is (at least to me faster- especially pressing the back button) snappy.
I hope that this lasts. Perhaps someone can confirm/ reproduce this phenomena on a similar machine.