Remember that you'll have to add the line to the /etc/init.d/rcS again in your cloned system. You have only activated the swap for your original Maemo so far.

To check if everything worked fine, run
in your terminal, and it will probably show your ram and your swap there.

To see if you're actually running the cloned OS, Settings -> Control Panel -> Memory. You should see there that the "Device" section has all the memory you delegated to it, and your internal / external memory storage (the lines below, If I remember correctly) should probably show around 450mb internal, 8gb external. =)