Ok so I did some more research and now I'm not entirely sure if the IWPG Heavyweight Title is considered a World Title. Also, Kurt Angle's reign as PPW Heavyweight Champion (Power Pro Wrestling) is what brings him to 13 world title reigns. But if the IWPG and the PPW Heavyweight Titles don't count, then Kurt Angle is an 11 time World Champion.
My next point is that while I was doing research I discovered that the current active and prominent World Titles are:
1. WWE Championship
2. World Heavyweight Championship (WWE)
3. TNA World Heavyweight Championship
4. NWA World Heavyweight Championship
5. ROH World Heavyweight Championship
This goes to show that the ROH World Heavyweight Title is infact recognized as a World Title. This means that for example, CM Punk is considered a 5 time world champion (ROH-1, ECW-1, WWE's World Title-3). It also means Daniel Bryan (Danielson), Kaval (Low Ki) Homicide, Desmond Wolfe (Nigel McGuiness) and Seth Rollins (Tyler Black) are all former World Champions.
I also found that that ECW World Title is considered a world title from August 27, 1994-February 16, 2010 (Ezekiel Jackson wins and retires title).
The defunct titles that are recognized as World Titles are:
1. AWA World Heavyweight Championship
2. ECW World Heavyweight Championship
3. WCW World Heavyweight Championship
4. WCW International World Heavyweight Championship
Really, I'm pretty confused on what is actually considered a World Title but what I got out of all this is that these 9 titles are the main recognized World Titles in proffessional wrestling. Here's the link (I got most from wikipedia) if you want to look at it.
http://en.wikipedia.org/wiki/World_...sional_wrestling)#Other_notable_championships