Is there anything particularly innovative about the Olympic Stadium designs?
The design has been conceived with two roles in mind - a full blown 80,000-seater arena in Olympics mode, substantially reduced to 25,000 seats in its "legacy" role.
It has been designed to allow that transition to happen, with temporary seating and roof, that can be re-used.
The design therefore needs less steel than others of a similar size. It also benefits
from the inherent stability of being built into a bowl.
The main innovation is the use of an 860m fabric wrap around the outside of the stadium, (the same as 72 London buses) which will be creatively lit with images projected onto it to give it vibrancy and a "life of its own".
Afterwards, the fabric will be cut up and turned into souvenir bags!
Will the designs go down well with the public?
Callers to BBC Radio 5 Live have predictably mixed views. It does not have the wow factor of Beijing's "bird's nest" design but neither does it have the engineering headache that have gone with it either.
Iconic architectural statements like the Wembley arch and the roof on the Athens Olympic stadium are all well and good, but cost a lot, and are not flexible.
There is no need for this stadium to remain an 80,000 seater - Wembley and Twickenham already exist in London - it has to be fit for purpose post games, and not a burden on the local community, so its "shrink-ability" is both clever and pragmatic.
I think it is a well executed design given the constraints placed upon the architects.
How much will the stadium cost to build?
We can take a guess that the £496m allocated for it will not be the final figure, and no-one is likely to suggest it will come down.
Equally, the organisers will not make themselves hostage to fortune by pledging not a penny more.
The bottom line is there is a huge contingency fund already included in the overall games budget and if some of that gets diverted to the stadium, no-one will be surprised.
The original price quoted in the bid book, about £280m, was at 2004 prices before inflation and VAT.
The International Olympic Committee asked for the costings to be presented within those parameters.
They have now changed the bidding conditions, and in the future cities will be asked to index costs to outcome prices in the year the games will be staged.
Does it represent value for money?
It's a hard question to answer because no two stadiums are the same or commissioned at the same time.
Athens adapted an existing stadium, spent £100m on a roof that almost wasn't finished on time and attracted a huge amount of criticism.
But it looked great on the TV pictures, and helped project an attractive, positive image of the city and the country.
How long will it take to build?
Hopefully less than five years.
Joking aside, they are already clearing the site, and groundworks should begin next April three months ahead of the original schedule.
This may be stating the obvious, but the sooner it is done, the better, because they will have to carry out test events to make sure it works for track and field during the games, and to identify any problems.
In a perfect world, you want it done a year ahead of the opening ceremony. But it's the unforseen they really need to allow for. Major projects like this almost always hit delays, so they need to build in a buffer.
Are there any potential pitfalls?
The soaring price of steel, workforce issues, colonies of crested newts?
The day after London won the vote, the London Underground was bombed and the security implications, (ie costs for the whole project) probably went up by a factor of 10.
The pitfalls are many and unpredictable. The Olympic Delivery Authority will be hoping to prepare for and anticipate most of them, but some things you just can't plan for.
There will undoubtedly be an element of luck involved in getting it finished well before the deadlines and not over budget.
What happens to the stadium after the Olympics?
Big changes to the proportions, as already described.
It keeps the athletics track and provides a permanent home for major track and field events.
It will also be accessible to the local communities in the five surrounding boroughs and an anchor tenant is being sought to help pay the maintenance bills.
That might be a football club, Leyton Orient perhaps, or a rugby club such as Wasps or Saracens.
Those negotiations are continuing, but not complete, and it will become a source of major concern if they can't sort that out over the next five years.