At a recent wedding in Jerusalem, I noticed the following differences from the practice I have got used to in the UK. (I realise this question could be asked to justify UK custom in the face of the custom in Jerusalem; please allow it in this form).
My questions are (1) whether these differences are special only to Jerusalem or whether they exist elsewhere and (2) the sources of the differences and if any reasons are given for them.
Difference 1: cup is broken after the 'erusin' blessings and before the seven blessings of 'nisuim'. (In the UK after the seven blessings of 'nisuin'.)
Difference 2: Witnesses sign the kesuboh under the chupah after it has been read up to where they should sign. (In the UK before the chupah.)
Difference 3: The Chosson signs the kesuboh. (In the UK he does not sign.)