When I updated Skyrim on Playstation 3 on the launch day, It downloaded a 2.0 update. On the in-game menu it says 1.1.20.0, why is it not called 1.1?

It is not labeled 2.0... it is 1.1.20.0 which is the 20th series of 1.1

Normally for patch versions you disregard everything after the 2nd decimal. However, that depends on the game's patch naming system.

I understand this however the patch on PS3 is labelled 2.0 - When downloading the patch which is around 50mb it says 2.0 (This is the XMB system interface). Only when in-game on the pause menu it says the1.1.20.0 in the lower corner.

Oh I never noticed the tag on the XMB... I don't watch my install screens

My Mistake. I only ever pay attention to the patch version within the games.

It just seems strange that it is called 2.0, the next update that comes out will have to be 2.1 or something. This is going to make it weird when looking for the change lists of patches.

i noticed this the other day.i presumed i had downloaded a 2nd patch as its defo down as 2.0 not 1.1 as advised. in saying that though i have not had any issues with the game that are deemed as un-playable or causing serious lag

How big is your save files?