5
The Bitcoin Wiki don't say much about fees, more precisely if you have a choice between speed vs. fees (pay more, deliver faster).
In fact, I don't yet even have a clue how fast are bitcoin transactions. Sometimes instant, sometimes it is structured by the wallet provide for lower fees but takes up to 24 hours?
5
A wallet provider might make it seem like the transaction is instant, but it will have to be included into a newly mined block (happens about every 10 minutes), for it to actually "go through". If you only pay a low transaction fee, it might take some time until a miner decides to include your transaction.
After that, it's up to the receiver of the transaction to decide how many blocks to wait until he books it as confirmed on his side.
The default client waits for six of these so-called confirmations to show the transaction with a checkmark.
"but with the high difficulty the network has grow to, it is sensible to accept a small payment already after the first confirmation without fearing for double spend attacks" this is totally wrong. The difficulty auto-adjusts with the total hashpower, so the % of the network which you need to perform an attack stays the same, hence difficulty going up doesn't make you less vulnerable to attacks. – o0'. – 2013-03-20T10:01:32.083
You will always need a certain percentage of the total hashpower plus some amount of luck to pull of a double-spend. But the total hashpower went up by several magnitudes of GHash/sec over time. I don't get your point, are you saying double-spends are just as easy to pull of right now than they were 2 years ago? – Philip Frank – 2013-04-02T15:35:59.590
Related: http://bitcoin.stackexchange.com/q/4483/516 (If you feel this answers your question, let us know and we'll close it as a duplicate)
– Highly Irregular – 2013-01-22T21:37:45.923Thank you for letting me know. On that thread, there is not definitive answer as well and also they are examining the question from the point of view of vetted developers and I as a newbie user. Thank you. – superuser – 2013-01-23T10:53:16.453