I recently contacted Nominet about a .co.uk domain that I was expired and detagged about how long it took to delete them once they've been detagged, this was the response I got, hope you find it useful:

Hi

Thank you for your e-mail regarding the acronyms.co.uk Domain Name.

At the time of renewal Nominet UK will invoice the Legal Registrant directly
with regards to the renewal. Ultimately, if the Domain Name is not renewed
it will be suspended and cancelled.

Where a Domain Name shows as being suspended it is pending cancellation. If
Nominet UK does not receive payment within 6-8 Weeks from the date of
suspension the Domain Name will be removed from our data base and will be
available for re-registration. Unfortunately, due to the first come first
served rule, we cannot give an exact date for the release if payment is not
received.

I hope that this is of assistance however if you have any further questions
please do not hesitate to contact me.


So 6-8 weeks from suspension to deletion, I have no experience with Nominet and deletion of domains, we'll have to see how well they stick to their word, it seems a lot better than NetSol and the forever expiring domains/non-existent customer service (my reply took <24 hours) though,

Tom

P.s. I've obviously changed the name above so don't say it won't expire soon (at least I hope it won't ;)

Keep us updated Tom. I've not seen one returned to the available domain pool yet...

-t