We would love to design iMac stand for iPen 2 if we have enough funding. You can also check out the wall mount at the Apple Store http://store.apple.com/us/browse/home/shop_mac/mac_accessories/displays
Yes, iPen 2 has palm rejection. In iMac, its screen is not a touch screen, so iMac will only register the iPen 2 signal, not your finger. In iPad, we're asking app developer to turn off iPad multi gesture feature while connected to iPen. This will avoid the conflict between iPen palm rejection and iPad multi gesture feature.
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