Well this was a different take on a very old and overdone story that actually worked a lot better than I expected. :)
The casting characterisation was great - i especially enjoyed all the banter between characters and the way the characters were set up in the begining of the series.
Sets were great and linked in to the sort of style of BBC's Robin Hood, which was also a fave of mine. The twists on some of the historicale details like Mordred and Morgana have proven to have had good grounding in this series in set up for the next.
My only problem with this series was how nearly every episode seemed to haev the same sort of format - Everything normal, something bad happens and either Merlin or Arthur are in danger, one of them saves the day with help of Gaius and Merlin nearly shows his magic side and eveything's good again - thankfully they did something about this in the next series as it was all rather predicatble.
Otherwise, a very entertaining, light-hearted and easy to watch programme for all age groups. Highly reccomended for families. :)