At the moment it's unclear whether this applies to other laptops in the MacBook range, but considering basically the same technology is used throughout, results will be similar. I have been using the Flash-blocking ClickToFlash plugin for the past few weeks on a 2009 MacBook Pro, and also noticed battery life improvements, but more importantly, the laptop does not get as hot when it displays multiple tabs with Flash content in the browser.
It's worth noting that Microsoft hasn't been bundling Adobe Flash with Windows since Vista came out in 2007, though an ActiveX control allows users to automatically install the plugin via placeholders within a webpage. Microsoft also kept clear of Flash on its new Windows Phone 7 OS, which doesn't support the technology.
The revelations in the toll Flash takes on laptop battery life shed further light into Apple's resilience into enabling use of the plugin on its line of streamlined iOS devices (iPhone, iPad). Apple CEO Steve Jobs made it clear chances of getting Flash on an iOS device are very remote, because of the strain it puts on battery life.