I have an au2 v8 ute is it normal that the motor has a ticking sound at idel? & how much differant is the standard v8 to the v8's in the xr8?

No it shouldn't really tick at idle. There are several causes, often it is actually an exhaust leak around hte headers but it could also be a loose rocker or a lifter that is not pumping up with oil. I wouldn't worry about it too much unless it is loud, an exhaust shop should be able to rule out a leak, after that you would have to remove the valve covers etc.

Difference between XR8 and standard V8 includes better camshaft, exhaust system and EEC programming, and if it is a 220kw motor it also has ported heads and intake, different rockers and larger throttle body.

It can also be injectors? It's normal for them to make slight ticking noise..But usually only heard when bonnet is open...
Cars with good extractors can sound like this also....
But if its a quite prominant tap it'll be rockers or clearance in valve system....The adjustment on these from factory is alittle hit and miss...They should have come with adjustable roller rockers....

I had a fairly bad tick at one stage, but a few months ago I flushed the oil (as usual) with the genuine motocraft filter and put some better plugs in her.. Seems to be gone now.

So true My XR8 AUII makes that noise from the extractors and it's great

just check to see if the sound actully is comming from inside the left gaurd it may just be the fuel purge thiny had me scared when i got mine only to find out most aus do it and its been doing it for a while now