It's somewhere in the 15~30 meter size range (being rather generous), so I don't see how it's the "end of the world." Unfortunately since we only got 5 days of observations of it ~8 years ago, the uncertainty in the orbit is quite high. The close approach date is so loose it's plus or minus 2 days almost 3. An impact isn't in the cards though; at most it will be only slightly close to us than YU55 was. Should be interesting to see if it's caught at all during its return; if it happens to miss by the maximum distance it won't get any closer than 10 million km, so the range of possible distance is quite huge.