I noticed this at first when I was viewing this page from my macbook pro and left hosts.sh active for a while. My computer got really hot and my computer fan started getting really noisy. I don't remember this happening on DD-WRT on the connected hosts screen. Also this doesn't seem to be an issue on other pages like:
bandwidth.sh
overview.sh
etc.
I tried this and the same thing happens with:
Google Chrome
Firefox
I also noticed that there are options to set the refresh rate of the page to never on:
conntrack.sh
I think options like this could benefit my CPU if implemented in:
hosts.sh