The hardware requirement for OS X Lion is pretty standard with the requirement for a minimum Core 2 Duo processor. You can check your processor type by going to > About This Mac to check if your Mac is up to the task of running Lion.
Lion requires an Intel-based Mac with a Core 2 Duo, i3, i5, i7 or Xeon processor and 2GB of RAM. The Lion upgrade can be installed on all your authorized personal Macs.
What’s not 100% clear is the delivery of OS X Lion. We know that it will be available through the Mac App Store but if that’s the only place it is available from then OS X Leopard users will first need to upgrade to OS X Snow Leopard before moving up another level to OS X Lion.
This is because the Mac App Store is only available on Snow Leopard. Snow Leopard currently costs $29.00 to purchase from Apple. If it is the case that those running on Leopard will first need to update to Snow Leopard before getting Lion, it will result in some users having to fork out just under $60 to make the upgrade.
Pricing & Availability Mac OS X Lion will be available in July as an upgrade to Mac OS X version 10.6 Snow Leopard® from the Mac App Store for $29.99 (US). Lion will be the easiest OS X upgrade and at about 4GB, it is the size of an HD movie from the iTunes Store®. Mac OS X Lion Server requires Lion and will be available in July from the Mac App Store for $49.99 (US).
Whether or not Apple will provide a boxed CD option for upgrading to Lion that bypasses the Mac App Store remains unclear. It looks unlikely though.