Buggered if I'm walking all the way round from York Way to Pancras Road to lock up my bike on platform 0!
Platform 0 is on the York way side though.
Er yes, exactly.
At the moment, it's very convenient - my train tends to arrive at platform 2, and in the evening, it's usually platform 1 or platform 4. The racks have plenty space, and seem relatively secure. I head off down King's Cross Road, so I can be from train to street in a few minutes.
If, however, I'm forced to go around to Pancras Road to get in, back round to platform 0, and back to platform 4, cutting across rush hour crowds with a great big bike and panniers, it'll be a bit of a pain. And I'll likely miss the train I currently get.

The only downside for me is closing the exit from Platform 8 towards St Pancras. My morning train normally arrives in P8 and that cut-through saves a few minutes on teh connection for Blackfriars.
Here's what you need to know:
Entrances
All entrances to the station will be under the glass canopy:
On Pancras Road
At the front of the station, just to the left of the old entrance (behind the Tube)
Two new escalators to and from the Tube
These entrances are closing:
At the front, under the green extension
York Way
Exits
From platforms 0-8
At the front of the station onto Euston Road or York Way
The exit from platform 8 towards St Pancras will close
From platforms 9-11
Exits will not change
Ticket barriers
There will be ticket barriers at all platform exits, so keep hold of your ticket.
Buying tickets
The old ticket office will close.
There will be a ticket office and machines in the new departures area.
Platform access
9-11 - access is not changing.
0-8 - two new access routes:
Through the ticket gates near the end of the platforms
Via the mezzanine bridge - lifts and stairs give access to platforms 0-8
What's happening to the old concourse?
It will still be accessible by those travelling via platforms 0-8.
The ticket office will close.
The shops will remain open.
After the Olympics, we're restoring the original facade and opening a public square - read about our plans.
Toilets
New accessible toilets with baby care facilities:
By the entrance to platforms 9-11
On the mezzanine
The men's toilets on platform 8 are closing.
The women's toilets with baby care facilities by the York Way exit will stay open.
Taxi set down point
This will move from York Way to the other side of the station, by the new entrance on Pancras Road.
It also says no exit from platform 8 towards St Pancras
I usually use this exit at the moment - so will need to be in the front unit of the train from now on.
OK, I assume they will take the gates away from the passage between 8 & 9 then.

There is a sign now on P9 directing passengers through the "Harry Potter" arch for P0-8, so it looks like the gate will go.
Will passengers still be able to take the "short" rout to the Victoria/Picc lines via the old entrance? Or are they forced to do the marathon through the new Underground maze? Or is there a new wonderfully convenient route to the Vic?
Coming from the Vic / Pic will be more painful as those barriers will be exit only (for how long until passengers complain?)...
Once the front concourse is pulled down, what will be the benefit of wanting to get into the station through the front (exit) barrier line?
The waiting area, catering facilities, ticket office, PIS displays and PA announcements will all be round the side in the new concourse.
It's much shorter.
It's all very well having waiting areas, shops, cafés, loads of displays, etc, etc, but if you're commuting, you just want to get on your train and go as easily and quickly as possible.
Plus, not everybody arrives by Tube. Plenty arrive by foot, bike and bus at the York Way end. It's also a very popular taxi drop-off, that saves having to go round the houses.
It's much shorter.
It's all very well having waiting areas, shops, cafés, loads of displays, etc, etc, but if you're commuting, you just want to get on your train and go as easily and quickly as possible.
Plus, not everybody arrives by Tube. Plenty arrive by foot, bike and bus at the York Way end. It's also a very popular taxi drop-off, that saves having to go round the houses.
Though many of the taxis are not dropping off in the official area - I think it says no stopping - many drop off immediately outside the arch to the York Way entrance.
I suspect that's typical of many busy areas, at stations and elsewhere, wherever there are designated ranks and drop off places. Do the TfL taxi people ever enforce whatever it is the council planners have insisted upon?
I share some of your concerns (but also remain to be persuaded - frequently being with bicycle, my needs are just a little more demanding than that of many others) but I think half an hour a day is an immense exaggeration (I'd be in Oxford Street and back in 30 mins).. . . . . I really do hope they come to a sensible compromise, or else this change is likely to cost me half an hour a day!
I share some of your concerns (but also remain to be persuaded - frequently being with bicycle, my needs are just a little more demanding than that of many others) but I think half an hour a day is an immense exaggeration (I'd be in Oxford Street and back in 30 mins).
I'm probs as eager as you are to see how effective the station is for cyclists. At present, I use some quite ideosyncratic ways in and out of Kings Cross, (dependent on my direction of travel) and the York Road entrance has been quite a great asset for travel in most directions, particularly with its proximity to racks between plats 0 and 1. Only using the station a few times will tell us what routes (devious or planned) remain.... You can see where this is going.
Just got an email promoting the new facilities, which includes a photo of the new FC lounge. The colour scheme is....how shall I say....different. :?