What Modemlooper said. It works just as it would with a regular WordPress blog without interacting with BuddyPress in terms of the poll results and functionality.
I’m currently looking for something to handle polls myself. For PollDaddy I simply installed it as a regular plugin, pasted the short-code into a sidebar widget and it works as expected. What it does isn’t changed by BuddPress in any way from what I can tell.
As for Intense Debate, it wouldn’t let me register with my WordPress account so not sure