Updated the OP with a list at the end.
Just as illustrated by what
@TakeAChance and
@Hollywood DMS wrote above, some tournaments are very hard to put in a majors/regionals category. That's why I'm currently tending to call those big regionals/small majors as "minors" in a category of their own.
So, for now, just to play along, could you help out categorizing the tournaments at the end of the list in majors/minors/regionals? After a while, if we wipe the "minors" category, then we just put all of them under majors, and label some minors as regionals if needed.
So, as of July 20th 2015, the list looks like:
Grand Slam: EVO (NA)
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Majors (and Minors)
While it is not established otherwise, I'll put them temporarily as Majors (maj) and Minors (min). It is absolutely open at this time. If anyone has a different opinion about any specific tournament, please post and we'll try to reach a common denominator.
NA: CEO (maj), Northwest Majors (min), Toryuken (min), KIT (min)
EU: Dreamhack (maj)
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Regionals:
NA: Texas Showdown, MWC
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To be classified:
MKX Asia Pacific Championship
VSFighting - UK (major or minor?)
The Commonwealth - US (major or minor?)
ComboBreaker - US (major or minor?)
SoCal Regionals - US (major or minor?)
NorCal Regionals - US (major or minor?)
ECT - US (major or minor?)
The Fall Classic - US
Winter Brawl - US (major or minor?)
Final Round - US (major or minor?)
Summer Jam - US (major or minor?)
NEC Championships - US (major or minor?)