There were opinion polls on Feesch as far back as October 1999, but they were scrapped in August 2000. Group Polls are different because they are group/event specific and can be created by the organiser or assistant of any group or event.
The advantage of this is that they can be targeted at a much more specific group of people and there's many more people creating them which leads to greater diversity and interest.
They can be used for settling a topical dispute purely for interest, eg "who was the best Star Trek captain: Kirk, Picard, Sisko or Janeway?" Or they can be useful for making democratic decisions, eg "should the event be held in a pub, club or restaurant?"
There are no limits to the number of polls a group can have and there is no need for them to be deleted. When a poll is closed (by the organiser or assistant) it remains available to the members of the group so that they can see the results.
There is also no limit on the number of choices each poll may have, though in practice it should generally be between two and ten. There is also a "no vote" option provided so that people can show the matter is important to them, even if they don't like any of the choices available.
For example, an event organiser might ask, "when should we have the event: June 10th or June 24th? If sufficient people choose "no vote" then the organiser might want to think about other possible dates for the event to maximise attendance.
Only the organiser and the assistant can view voting statistics while the poll is open, it can be closed whenever they feel the majority of people have had their say. Once closed, everyone in the group can view the results. However, at no point can anyone see how anyone else voted (that includes the organiser and assistant), voting is totally private.
Great care should be taken to avoid influencing the results. The question should be worded and the answers selected in a way which does not effect bias. It might however, be necessary to give some context. "best captain" is very open to interpretation, do you mean "best leader" "best actor" or just "best looking"?
While organisers and assistants might feel group members would be interested, the state of current voting should also not be disclosed until the poll is closed. For example, if someone said, "Picard is winning by a mile" then those fans of Picard might feel it unnecessary to vote, while their opponents might suddenly feel an extra incentive to vote for their choice.