You should have a conference tag!
In addition to Sports, Technology, etc. you should have an option to choose Conference because so many hashtags are being used for discussion of conferences (like TC50, #140conf, etc.). Some are technology conference but others are more social media or on other subjects where none of your tags fits.
You also might consider adding TweetChat or Webinar for hashtags used for live conversations on Twitter and an option to "untag" a TT that has been tagged inaccurately. Once an option is chosen, the editor can only choose another tag and sometimes none of the choices fits.
Maybe also separate "world" & "business" because they are two different things. How about a "news" & "business" instead? Although I think I'd get rid of "business" altogether since not many trends are strictly about business topics.