Not too many, but bear in mind that DL is significantly larger than CO, so the valuation isn't that surprising, at least vs CO. Personally, I think the whole industry is too messy to really get involved with financially. I mean, CO looks good now, but bear in mind that they are probably the only carrier that sees anything positive from the run-up in oil prices, given their IAH hub. Also, they have been successful building up out of EWR internationally, but will this hold out as DL ramps up and the Open Skies agreement lets everybody in on the game? None of the other majors have any fewer question marks.