Transactions per block

[iamtheone]

By design, can bitcoin sustain a sudden surge in number of transactions? How many transactions per block is allowed?

[theymos]

There's no specific limit on the number of transactions, though blocks can't be larger than 1MB and most miners won't create blocks larger than 250-500 kB.

[iamtheone]

In your estimate, how many transactions will that be? I mean just simple transactions. What will happen if there will be so many users of bitcoin, will that mean sending coins will be delayed?

[theymos]

3500 transactions, maybe.

What will happen if there will be so many users of bitcoin, will that mean sending coins will be delayed?

Transactions with the default fee will be delayed. Transactions with higher fees will get priority.