There was no world cup held in 2007 only.
about 30-40 mil
it is worth about 250,000
If the shirt is match worn by Beckham with a credible cerificate of authenticity (CoA) then it is worth £500-£800. If it is only a replica shirt then £150-£250 (if you have a CoA or photo of them with the shirt).
Its over $9000
100000000000 billion
This depends. If you want to remember the night then yes, because the shirt can serve as a reminder of the night.
The shirt probably won't be worth much since the very first night game was 8/8/88.
It depends on the shirt (t-shirt, replica jersey, authentic jersey, etc.), it's condition and who signed it.
£40
Probably nothing more than any other t-shirt...
$250
60%