Another fun thing is to look back at the strongest alliances and see which ones aren't even around anymore:

(Listed in order of 1st set TNW):

1) LaE: Sort of still exists, as KA.
2) Dynasty: Gone when Skystormers retired.
3) RoCK: Gone after set 1. (I'm guessing the Hellrush revival of RoCK was a different group?)
4) AoDT: Seemingly got sick of continual wars with NBK and gone.
5) SYN: Beat down by LaE in 2nd set and never returned.
6) IPU: Not sure who they are, but they disappeared.
7) ROME: One set here, too.
8) PanLV: Very small in that first set (49 countries), but still exists.
9) ABC: If I recall correctly, this is basically the predecessor to FoCuS. So basically they do still exist.
10) NYG07: One-man tag, apparently a Giants fan. Tag was gone in 2nd set.

And 10th in Membership, but further down the list due to war:

NBK: Still exists, probably the one alliance that is as close to the same now as it was at the beginning, as a large warring alliance.

So seemingly, from set one:

Only 2 of the 11 alliances listed above exist as is: PANLV, NBK

2 more alliances could be argued that they're the same outside a name change (Very definitely for ABC/FoCuS, more questionable with LaE/KA, but they're basically the same central group).

7 more alliances don't exist at all.

Meanwhile:

2 of the top alliances now seem to have gotten their start in set 2 (IMP, TKO).
And one more in set 3 (SoF).