Separation - taxation queries?

Newly separated.

have read a lot re taxation etc. other half is assessable spouse - tax from my reading says that other half with be taxed for all their wages for '09 plus mine up to date of separation - will have full marraige credits and cut off. then i will be taxed as single person credit plus paye credit with single cut off.

am i correct?
If i notify the tax office now, will this come into effect straight away?

next year i will be taxed as single person, do i get only one single allowance as will be single parent and how will other half be taxed next year - from my reading its that they will have married credits with single cut off?

one last thing, as my name will still be on mortgage, can i claim a rent credit? - not the most important thing obviously but on my mind.

yes you are correct and it will apply straight away.

you will both be taxed as single next year but you can both claim one parent tax credit if you satisfy the conditions.

you cannot claim both mortgage interest relief and rent relief in same year

ok, when i call the tax office to notify them, do i need to have both our gross wages to separation date? or how does it come into play straight away?

Also do i get a full single credit and paye credit for the year... or is it apportioned from date of separation to the end of the year?