I seem to remember satoshi justifying the 10 minute interval as roughly the amount of time needed to ensure world-wide propagation of a block and reduce the occurrence of stale blocks.
That's what I remember from old threads as well. I managed to find one such thread where DeathAndTaxes explains it nicely. The 10 minute block time and small block size results in only a tiny percentage or orphaned blocks. If the block time and size was bigger or were to be increased, that would result in more orphaned blocks and less network security.
Any block interval is a compromise. 10 min, 1 min, 60 min, etc. There is no right or wrong. It is a compromise. Remember the actual block time will vary. When blocks can't propagate the network fast enough and competing blocks are produced that results in orphans. The % of orphans direct reduces the security of the network. Currently Bitcoin w/ 10 minute blocks (and relatively small blocks) has about 1% orphan rate. That means 1% of hashing power is wasted and doesn't improve security. As blocks get larger the orphan rate will rise (although faster CPU and higher bandwidth connections improve the orphan rate).
10 minutes is a compromise between confirmation times and network security. Really unless you are accepting 1 confirm txs faster block interval won't make tx validate faster. If you wait for 6 confirmations on a 10 min block chain then with equivalent hashpower you should wait 24 blocks on a 2.5 min block chain. If you are willing to accept 4 confirmations on a 2.5 minute blockchain then 1 confirmation on a 10 minute blockchain provides equivalent security.
Really a shorter block interval only helps if your business accepts 1 confirm txs (because 1 confirm is always more secure than 0 confirms regardless of the block interval).