I saw his a few days ago and it seems absolutely geekalicious. The Doctor Who Experience.
It’s an immersive interactive experience inside the TARDIS with video participation by the Doctor (Matt Smith). From the web site:
Packed with amazing special effects and exclusive filming with Matt Smith this multi-sensory experience is fun for the family and fans alike. This interactive journey takes you and the Doctor on a spectacular adventure though time and space. Step though the crack in time and help the Doctor, armed with his Sonic Screwdriver, escape from his enemies, fly the TARDIS and come face-to-face with some of the scariest monsters seen on screen including Daleks, Cybermen and the Sontarans.
There is also a tour guide company offering Doctor Who tours. The tour starts out at the Doctor Who Experience then moves on to different Doctor Who and Torchwood filming sites around Cardiff.
I really want to go.