How do I check which version I have? I want to make sure I am patched!

go into windows explorer

go to the steam folder and into the fallout nv folder

C:\Program Files (x86)\Steam\steamapps\common\fallout new vegas

right click on falloutnv.exe

go into the properties and check the version. it should be 1.2.0.285

Also, you can go to display options in-game. Version number should be seen n lower-left corner.

true.. but if you are smart and want to roll back the falloutnv.exe version and you have windows 7 you can do it from the properties page or you can copy the old exe's to a folder and keep the 3 diffrent versions and mix and mach at your whim (which is what I've done).