It depends on what you call similar I guess. To me - they are barely similar at all.
Screen size? Galaxy (7in); Adam (10in) - For me, a 7 inch screen is barely worth it. I want the larger screen to really enjoy what I am doing. But to each their own.
Screen type - G (lcd only); Adam (lcd & eReader style for reading in full day light). This dual screen capability is key for me as I do a fair amount of reading. Having one device that serves two purposes in this way is a great feature.
Camera - G(two cameras front/back); Adam( 1 camera that swivels front to back). This is not a big deal but it does feel more flexible to use.
Ports - G(30 pin dock to interface to other types); Adam (3 usb ports, hdmi port; sd card)
GPS - G(no?); Adam (yes)
Cost - G($700); Adam ($500 fully loaded)
There are other subtle differences too and I really like the OS on the Adam in how it plans to handle apps. Its just no contest to me. The Adam has everything I wanted/dreamed about in a tab.