We're required to use the corporate booking tool, and this message was loaded recently about the Frontier seating change:
As of September 12th, 2012, Frontier Airlines will continue to offer advanced seat assignments in classes Y, B, H, V, L, U, E, D, S, N, and A. Their lowest fare tickets, M, Q, T, G, W, R and Z, will have seat assignments available at the time of check-in, including on-line (24 hours in advance), kiosk, and airport.
Passengers who have Ascent and Summit elite status on Frontier, will continue to receive advanced seat assignments in any booking class. Ascent members will continue to have access to SELECT seating, at the front of the plane in rows 5 -10. Summit members will have access to any seat on the aircraft in advance, including STRETCH seating, which offers at least 36 inches of pitch in rows 1-4 and the exit row.
Classic Plus and Classic passengers will also continue to have access to advanced seat assignments in all fare classes. Seat assignments for M, Q, T, G, W, R and Z can be obtained by calling the Travel Agency Desk at the number below.
No indication of frequent flyer earnings changes here, although I'm not surprised since the corporate travel service isn't concerned about our loyalty points.
As for Southwest (since someone else asked about it in relation to a corporate booking tool) we've had it available right along with other flights for a number of years. However it appears to be a separate system interfaced in, because in some ways it displays Southwest like all other airlines, but in other ways you have to "click through" to get comparable information. There are certain different rules for how to handle changes, cancelations, and refunds compared to other airlines as well. But it's better than a handful of years back when booking Southwest could not be handled with the online tool.