Morneau's slide would still be legal under the new rule. He went straight into second base. He surely started his slide a bit later than he could have, and clearly wanted to disrupt the second baseman, but he did not alter his path and slid right into the base and it looks to me like he could clearly stay in contact. The second baseman was held up by the throw, but this is a fair and good slide even by the new and improved rule. It goes to show you that when you purposely behave to make contact in a not contact sport and stretch the "spirit of the game" intentions, that instant karma can get you when you least expect it.
I think you could make the case that Justin would have slid 5 feet past the bag had he not hit the fielder. therefore he intentionally tried making contact.
If we get a couple fewer brain diseases, broken limbs, etc a year I am not sure what the downside is here.