I have an '07 Volvo with a 2.5 L turbo 5 cylinder. 233k miles and counting, not one turbo issue.
Only special maintenance I did was full synthetic oil, which I would do in any vehicle that I owned. Was never too picky about letting it run for 30 seconds before shutting it off, during normal driving I'm not being hard on the turbo.
Like the new 2.4, this Volvo motor is tuned for low end torque. It has a great driving character, I really enjoy it. It's not fast per se, but it's like a little diesel, it'll chug up pretty steep grades without needing to downshift from 5th gear.
Personally, I think the new 2.4 turbo is going to be a great drivetrain for the 4Runner.