I don't you people should be questioning the competancy level of an organization's people until they have been in their shoes. The people that is saying to migrate everything to common web front standards. Do you know what you are saying here?
In a large organization like Air Canada, they have literally hundreds if not thousands of systems. Some of them custom written by some IT person many many years ago and have left the firm, some are off the shelf packages, some are AS-400, some are Unix, some are NT, some are Mainframe, and believe it or not AC still have applications on the old green screen mainframes. To have all the different applications to run on the same platform at the same time is virtually impossible. This takes years of planning and migration is gradual. NOt a 1 year project or even a 5 year project.
A few years ago, I was part of a team that implemented a eProcurement & marketplace solution at Air Canada, we used Ariba as the procurement software, but there was over 20 Interfaces that needed to be custom written to inteface to their other systems, like their ERP which was Oracle, materials planning(a customer AS400 system they called ARTOS), etc...

In a nutshell, the example shows that a large organization like Air Canada needs time and good project management, and vision to migrate to a move integrated and common platform. As they have the resources(both people and money) to implement new applications, they will move from the legacy platform and onto the new one. Which application to replace first is based on priority and resource availablity. When they were in Bankrupcty protection, I think spending $50 million on system improvement is not at the top priority.

BTW - Those that state SAP is hideous, and JUST an accounting software, should back up what you are talking about.....
There is so much more to SAP, and other ERP software than accounting. What they should complain about is the organization and mangement that implemented the SAP is hideous.
If implemented properly, ERP softwares like SAP will bring tangible benefits to across all functions of the organizations. Ever heard of distribution using SAP to plan and execute sales orders, Manufacturing using SAP to control shop floors, control inventory, material planning, resource planning, scheduling, etc...I can go on and on.
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