I guess you're watching the new series with Christopher Ecclestone as The Doctor. Russell T Davies who wrote all the episodes turned in some good stuff. The later epsiodes getting better and better IMO. Also a new secondary hero in
Captain Jack.
Chris E bowed out after this series (I thought he played the role a a shade on the heavy side). His replacement
David Tennant looks to become an even better Doctor (we've seen one episode with him and he is definitely in the lighter, more eccentric mould of te Tom Baker sort) - the first of the next series with him in place begins this autumn over here. If you get a chance to see the series
'Casanova' in which he played the lead - it'll give you an idea of how he will fit in the Dr Who role. Interstingly, this 'Casanova' was also written by Russell T Davies - I wonder if that connection had anything to do with DT getting the Doctor role....?