I am a small business owner who has finally accomplished the task of getting my business partner to switch to a Mac. Hooray! We should get my partner's iMac in a few days. We already have a Mac Mini Server that we use for data management and file sharing, and I use a Macbook Pro. I bought the iMac, but we are sharing in the cost of the machine and the software. We will get a free upgrade to lion when it comes out. I figure that since I bought it, that I should be able to install lion on both my Macbook Pro and the new iMac. The problem is that we would use my iTunes ID to download the software I have already paid for. He may want to buy apps on his own and use his own iTunes ID (although he does not have an ID yet). If we install software using one iTunes ID and then later he creates his own, will that cause us a problem with getting software updates and will he still be able to use the apps purchased with my ID?