[Closed] 2010 shimano xt vs 2011 shimano xt help needed please

Hi. I just wondered if anyone could explain to me in layman's terms the advantages of buying 2011 10speed xt components over 9speed 2010 xt components please.
Sure i realise the gearing is different but ive no idea if that is a big deal when riding.

My general riding grounds are the peak district so lots of up hill riding has to be done, i dont know if that changes things??

The reason im asking is my local bike shop only has the 2010 9 speed group set in and im ordering the bike on tuesday and wondering if i should now wait for the 2011 spec 10 speed gears?

Thanks in advance for any help