Originally Posted by willyc
I am on OS 4.2 and i would like to know if there is any advantage to upgrading to 4.5? I would also like to know that if i do upgrade will i have to unlock the vendor themes again for the new OS?
Yes there are many advantages...just search the forum and you'll see the benefits.
And yes, you have to modify the blackberry.alx file to unlock all vendor themes.