My memory of Pandora is very fuzzy since I stopped using it over a year ago, but I seem to recall that I would occasionally have to close the tab (I'm talking after 15 hours or so) because it was just using up a lot of memory. I think it does a lot of local caching and doesn't know when to dump the cache.
I'm set up to run from a 2GB partition on an SDHC card (OS) and a 1GB SWAP. I am overclocked to 800Mhz using the stock tool. I haven't tried it at 500.
My network connection is via a Kensington USB mini dock with Ethernet.
It did -not- work under midori. Only under Firefox 5.
I'm pretty sure what eventually crashes it are animated advertisements.