It's funny, members were more worried about a number then the acually threads being lost. I don't hear anyone saying. "Man, i made a really helpfull thread, and now it's gone". I here, in my own words: "Man, i lost a stupid little number".
If it was gone, i wouldn't care much at all. I've been here for about 1yr 1/2 now, and i broke the 1000 mark like 6 months ago. That should show what i care about a number.
I also don't think they will get rid of it, seeing that WetWired created a nice little hack to use images as the numbers, instead of using text. So i don't see it going anywhere, anytime soon.
And if they used cron jobs, this would have never happened.