I need to buy an iMac before the end of December (for accounting reasons), and was thinking of buying one in the Black Friday sale, to get $101 (whatever that is in the UK) off the price of a Mid-2011 3.4GHz i7 iMac. The MacRumors Buyer's Guide says to buy only if I need it, as it's approaching the end of a cycle (about 10 weeks away). Are Apple likely to release an updated iMac toward the end of this year? Are there any rumours that point toward this? Thanks!