Actually i tried to do Blender's combos in all other 3D apps i've tried. And since they fail, i get frustrated

. Although if you think about them for a moment, you'll realize they make sense (well the most common of them at least): g for grab, s for scale, r for rotate, e for extrude, b for box selection, c for circle selection (in new version), etc.
Blender 2.5's ability to change keys is minimal to what /else/ this new release has. Its probably the biggest change on the program since 1994 when it was still a bunch of ideas in Ton's mind

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The new version has a brand new awesome UI (which is fully controlled with Python), a redesigned event system based on a concept of context+operators which can be applied using shortcuts, buttons, scripts, etc, multiple window support (which enables users of more than one screens to take advantage of their extra screen - there is actually a premade layout which contains almost every object property for just this reason), a new awesome Python console, help for everything, a revamped and *much* improved file window and my favourite: being able to search for operations and other actions: just press space, type a part of the name and enter. Do you want to repeat the action? Shift+R. Do you use action frequently? Put it in your toolbar just as easy.
The new version is a HUGE step towards usability. I'm using 2.5 since some months now and i can't go back to 2.49. It crashes a bit (although it improved since the nightlies) but the experience improvement it provides is worth it. Besides, it autosaves almost every minute, so its not like you'll lose much if it crashes

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