Minecraft 2.0 was an April Fools joke from Mojang. The joke was played on an audience through Youtubers (mostly Mindcrack).
Also, I don't think Mojang plans on releasing a Minecraft 2.0. Eventually in Minecraft 1.X (No clue on what X will be), there will be a major feature freeze (no more development, just streamlining the game so there aren't any bugs) and things will be left to mod developers (The modding API will be a valuable asset in this eventual transition).
So, if you see a youtube video about it, make sure it wasn't published near April of 2013. If it near this day, it is very likely to be a part of the huge joke that was played on the community. If it isn't, then it needs to be a reputable video with some actual proof for MC 2.0 to come anywhere close to being valid.
The title told me so! So did the thumbnail!
Some youtubers are known for misleading titles and thumbnails. Could be a Rick-Roll type video with "Minecraft 2.0" being the lure. We'll never know unless we can actually see it though.