Not authentic in my opinion. As far as I know (I could be very wrong), Michael didn’t sign autographs at the This Is It announcement conference. He was already about 2 hours late and I believe he left shortly after making his announcement. As for him signing this is London in general terms, I can’t really verify that. To me this seems like a slowly written signature that lacks Michael’s pen pressure points. The ‘J’ to me is off and the ‘H’ is too big. I do however like the ‘ic’ part in Michael, however he rarely wrote out his name fully like that in the late 2000’s.
I don’t think this is authentic either. This appears to be sort of a combination of old-style and newer-style MJ signing. I don’t think this would have been how Michael was signing items in 2009.
Also, Michael’s signature style in 2009 was very different than what’s on this CD album cover. Michael extended the ‘M’, ‘J’ and ‘N’ in his later signatures. Those three letters should be the longest and tallest.