No - I don't think a huge amount has changed. It was a mixed bag - some areas (the crocs and turtles, for example) were very good, and I liked the general 1950s atmosphere - but it is overshadowed a little by one or two enclosures that are just not good and by the generally quite slight collection (the latter also applies to SeaWorld Orlando to a slightly lesser degree - I think it's because the fish exhibits feel a little 'token' at both). There are only two species of shark, for example, despite two large tanks - and neither are 'classic' sharks (nurse sharks and bonnetheads).
To be honest, I've very rarely seen the programme, but even so it was quite fun to see - added a bit of extra interest. I did like how they are still using it.