So house arrest without trial seems to be off the cards:

In its place, Mr Clarke is proposing a system of
bespoke control orders that will grow in severity depending on the
level of threat posed by a suspect. They will apply to foreign and
British citizens and it had been envisaged that the most draconian
order would involve house arrest.

But ministers
have been taken aback by the outcry over the plans since they were
announced in the Commons last month. The two main opposition parties
have signalled that they might oppose the legislation and talks will be
held next week over how it should be framed.

Please don’t think me a dreadful cynic but this almost looks planned. Announce something outrageous, back down a bit ("See, we listen to the people") and then get what you wanted anyway. Curfews and control orders on whoever one pleases, whenever one pleases, with no recourse to the courts. This is still just as appalling as the original notion. The simple solution is to allow intercept evidence in court, just as is done in many other countries.