The mainframe view is what IT is accustomed to, never mind the actual technology deployed in the data center. It's a mindset that puts the enterprise applications in the middle, with human beings using computer terminals (now tightly controlled "thin clients") at the periphery. The enterprise applications manage the company's "core processes." The human beings perform process roles according to the rules laid out and enforced by the enterprise applications. It's the mass-production business model.
One problem: The mass-production business model fits fewer and fewer businesses, and even within businesses that still engage in mass production, fewer employees have mass-production jobs.
In mass production's place are an increasing number of business processes performed by single actors -- and often performed only once, to deal with an unexpected situation.
To understand how business processes are collapsing from assembly lines to individual actors, you can look at an item as prosaic as the interoffice memo. Once upon a time it was a four-actor process: The author wrote a draft longhand or dictated it. From there, it went to the typing pool, then back to the author for editing, then back to the typing pool. Next, the author's manager handled final editing and approval before being typed for signature. Finally, the mailroom delivered it.
Yes, little Johnny, that's how it used to be done back in Grandpa's time. The process commonly required days. It's now a single-actor process completed in minutes: The author composes an email, IM, or text message -- and sends it.
Increasingly, responsibilities that used to go from desk to desk are handled by single individuals who draw on whatever business resources they need -- mostly, those available through the computing device that sits on their desk.
It's the portal view of computing: The desktop or laptop computer -- and increasingly, the smartphone and tablet -- are portals to the array of resources employees need to handle modern business processes. That's a good reason to get away from the "single software image" mentality that denies users flexibility in the apps they use.
Along with this change is decreased reliance on standardized processes and an increase in the level of creativity required for success. Probably the best-understood example is the move away from standard reports to BI-driven analytics. The difference: Fixed reports answered whatever questions the report's designer knew to answer.