A database, possibly, just not an "enormous" one.

Her department, the Home Office, said one option being considered was a database that would store the phone numbers dialed, the Web sites visited and the e-mail addresses contacted by every one in Britain.
But while the who, what, when of communications may be retained the content of communications will not be stored:
"There are no plans for an enormous database which will contain the content of your e-mails, the texts that you send or the chats you have on the phone or online." said Jacqui Smith
There's in-depth reporting and analysis of Jacqui Smith's speech over at BBC News Online.
All this is inline with the claims we reported back in July The Information Commissioner's interview on WATO, conducted a few days after that initial report, has been widely quoted today.
And a reminder that if you haven't heard the podcast there's a timely discussion of a major US study into databases and the limits on their usefulness in combating terrorism. The discussion on the difficulties of combining different data-sets seems particularly relevant.