sub 2:00 marathon

Yes is the slightly longer answer.
But decades away.

Hm.. good point KK - what happens when sports, as all sports must at some stage, actually reach the limits of human ability?

There must be a limit to how high or far athletes can jump or cover a certain distance, even if you only end up with nothing but the tallest athetes with the longest legs.

Looking at the race-time predictor,1.59.59 equates to a 10k in 26' 04'' ,which isn't that much faster than the current 10,000 metres record,so maybe it's not actually that far away.

Imagine say,Wanjiru and Gebressalassie racing "head to head" with pacers at a fast course llike Berlin and I reckon it might be possible.

Mind you,the record I would love to watch someone break is the men's 3000 metres-every time I watch it on youtube I find it astonishing !

Difficult to know without knowing the extent of doping in marathon running.   Assuming it goes on then if there is a step forward in technologies used by cheats - say based on manipulating genes - then that could see a step forward in the kind of times that are achieved.    I mean if the current top runners are clean then if they used current doping methods - based on what you see in other endurance sports and the benefits in sustainable power output - the record could go any time.   If the current crop of top athletes aren't clean then the record is going to depend on future advances in doping.  

Haile is about a minute or so faster than anyone else has run , so when the next guy comes along and improves that record ( Sammy Wanjuri ??) we will be down to 2:03:00 ish and these records can last for a decade before they go. So if anyone does break 2:00 it might not be for a while.

By which time you could be going through drink stations and getting glucose injected straight into your viens

yes.

No problem.

I've just got to knock a few more minutes off and I'll be there.