Starting in February, United will take over Continental's Houston (IAH) to Lima (LIM) route.
Currently, Continental operates a 757-200 on this 3,143-mile, 6.5 hour flight, featuring 16 BusinessFirst seats (though this winter they will be transitioning to a 757-300 with 24 domestic first class seats). United, at least according to the seatmaps currently available, will be using a domestically-configured 767-300 for the route.
While this will increase the number of premium seats onboard (bringing the total to 34), a lot more economy seats will be added to the fray as well. That means upgrade chances will only be marginally better.
The question of the hour is whether this route will again become a complimentary upgrade route. Continental used to offer free elite upgrades between IAH and LIM, but stopped in March this year.
There may just not be enough paid premium traffic on this route to justify a three-cabin product, but LAN will surely have the advantage now in terms of premium offering. I don't think I'm the only one who avoids using a systemwide upgrade on a "ghetto bird" (as UA flyers call UA's domestically-configured 763s) if upgrades aren't complimentary.
Here's a look at one of UA's first new post-merger international routes: