I was searching for articles on point to point versus hub and spoke and came across an interesting presentation by Univ. of British Columbia School of Business. It states the following:

Average flight lengths are increasing.
Non-stop markets are increasing.
Frequencies are increasing.

Average aircraft size is decreasing.

In 1970 the average aircraft seat count was 130, and in 1990 about 185. The projection for 2000 was 215 and the actual count turned out to be 175.

The twin trends of increased point to point and frequencies will probably reduce the average aircraft size further. Link:
http://www.sauder.ubc.ca/cts/docs/Bo...vs-Airbus-Presentation-Dec5-05.pdf

Another interesting academic article points out that point to point carriers relative to H&S carriers have 36% lower revenue per seat, but an offsetting 46% lower unit costs, and overall, a 207% higher profit level. Link:
http://mywebspace.quinnipiac.edu/cba...ing%20Hubs%20&%20P2P%2008_2005.pdf