It's easier to build Blockland, you'll see. If I'm correct, you have to switch from some browser window if you want to play the game, and another program to build.
The physics, in my opinion, are more simple. ROBLOX' physics are server sided, so that means the person who's hosting, his computer calculates the physics and sends the information to you, which makes for laggy physics. Blockland's physics are clientsided, which means your computer calculates the physics itself, and Blockland has 5 levels of physics, based on how well your computer can compute physics. Basically, if your computer sucks, you'll have very little or no physics, and if your computer is really awesome, you'll have the best physics.
Also, not many people (at least with common sense) enjoy hating ROBLOX. In fact, some people play ROBLOX and Blockland too.