I had a rattle on the '08 Sport and I currently have a rattle on a '09 Lounge at the rear on the driver's side and both were linked to the standard shock absorber. When the shock absorbers were replaced on the '08 - rattle went away. On a '09 it hasn't affect the 'ride' but it's on the 'to do' list. Recent thread on here on someone having a shock absorber changed for an MOT test.
If the shock isn't the issue - you could check that it is not the hatchback lock - I remember there was a thread on it.
You have the space wheel - didn't have one on the '08 - you could check if the spare wheel is 'tighened down'.
:yeahthat:
Other thing to check is that fold down section of the rear seats are 'banged home'. Sometimes they sit in place but are not properly secured.#