While I admit, I do not really watch much of the Daily Show with John Stewart, if John Oliver is truly a pro at his craft, there is a much better opportunity to make a big name for himself by going to HBO. HBO is a huge deal in the entertainment world.
The daily show will not be the same without John Oliver, the long-time senior British correspondent for the show. However, if this is something that he wants to do, I would fully support it. I am sure it was a hard decision for him to make but if he has the opportunity to have his own show, that opportunity may never come around again, so I am glad he has done it. If it fails totally, I hope he gets to return to the Daily Show.