yep, i've been testing with it
and when they went from 0.15 to 0.2 i only had one issue with Zend_Config
which was easily fixed
not that i'm using a huge amount of the framework
but, anything that's in the library (not incubator) should be ok to use
but don't expect all code to work from update to update, especially while they're still only in preview releases
The framework is at 0.7.0, with just about all components being stable, I don't see why now would be a problem. As long as you keep update to date on any changes, it should be fine.
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