First I would like to ask, why constantly Halo is targetted by the gaming community as being a "milked" franchise, "too many games", "cash cow" so regularly, when including Reach there's only 6 titles, which is small compared to Call of Duty's 9 titles (10 when you include black ops), or Mario's hundreds, or Final Fantasy's 13 main series titles, plus the many many spin offs.
I think that's kind of a double standard.
In regards to this thread though, I do agree that Halo should be brought to an end after Reach. As much as I enjoy the Halo series (even Wars somewhat), I think they've reached the point where they can't add much more to the series. I think it would be good to end the series while it's ahead, rather than dragging it out.
Though I've noticed a few comments suggesting a Halo RPG, that could be interesting.
If Bungie stick to their comments saying Reach is the last Halo game anyway then this wont even be an issue.