User blog comment:-merlin12/Series 6/@comment-4623180-20111127104616

In an interview about what's happening after series 4, the main writer, Julian or whatever his name is (and I swear on my heart I saw this interview and this is true) said "5 series were originally planned" and I think he may have said we'll see where we go right after that, or something like that. The way he said it, he probably meant to say "we like the series like our fans do, if they demand more we'll just try and see how far we can go".

I mean, they don't have much more of an idea than you do. Time will tell. By then you may be sick of Merlin. (Nooooo!) But really, let's hope it doesn't get old and dry. :)