Last night at 8:00pm EDT both American and Delta matched the increase of $4 to $70 roundtrip initiated by United earlier in the afternoon.

This leaves only three legacy network airlines — Northwest, US Airways and Continental — yet to match their next chance to match will be at 10am EDT Friday.

United also showed some minor increase activity — firming up those few city pairs that were left out of initial increase at noon yesterday.

Both American Airlines and Delta Air Lines matched the increase by increasing airfares from 2% to 5% across the bulk of their respective route systems.

This increase attempt is now 15% short of the 20% called on by the Delta CEO earlier this week — he estimated it would require 15-20% in airfare hikes to make the airlines whole at $120 barrel oil.

These new priceswent into effect shortly after midnight EDT. Again, I cannot stress enough that consumers should lock in their summer airline travel as quickly as possible, especially on the remaining 3 legacy airlines that have yet to match as they are likely to match today and consumers who act quickly (before noon Friday) can save up to $70 roundtrip.