Priorities in Bitcoin-qt Client On the bitcoin wiki its says:


  Transactions need to have a priority above 57,600,000 to avoid the enforced limit (as of client version 0.3.21). This threshold is written in the code as COIN * 144 / 250, suggesting that the threshold represents a one day old, 1 btc coin (144 is the expected number of blocks per day) and a transaction size of 250 bytes.


Meaning 1 BTC need 1 Day to become medium priority and will need no fees. On testnet I collected a few coins and checked the priority in bitcoin-qt client. It grows from low to low-medium to medium. Then it stops. While now on 570 confirmations it should be way higher than medium priority. Checking the bitcoin-qt sourceode there are more priorities deposited.

Did I missed something?
The relevant source is this:

if (AllowFree(dPriority)) // at least medium
{
    if      (AllowFree(dPriority / 1000000))  return tr("highest");
    else if (AllowFree(dPriority / 100000))   return tr("higher");
    else if (AllowFree(dPriority / 10000))    return tr("high");
    else if (AllowFree(dPriority / 1000))     return tr("medium-high");
    else                                      return tr("medium");
}


The label only changes to something higher than "medium" when the priority is at least 1000 times larger than the minimum. Your priority is large (I estimate 570/144 * 27 = 107 times the minimum), but it's not that large.