I've only slightly used Blender. I can say that it has a similar learning curve as that of Maya... which is steep. But Blender IS powerful and packed full of features. I love the use of lattices, which I'm disappointed in Carrara for not supporting (been asking for this scene version 3). The shader system is different and (while just as powerful at Carrara's) is harder to produce the "look" you are after. You'll have to know the effects of contain shaders operations by text before you can really built shaders with it. Also, it uses some unique naming conventions for all aspects of the program.
Bones system is hands-down better than Carrara's... and it's being rewritten for improvements. Import and Export options are very high. Strong user community and often-times free phython scripted plugins.
Modeling is different. You are REQUIRED to use hotkeys to do just about everything. While this is a fast means of doing things, it requires a level of familiarity before you and do anything with the program. Best to have a keyboard guide at all times.
I have not touched Blender's game engine so no comments from me there.
However, I still prefer Carrara over Blender. Blender is probablly more powerful than Carrara but you'll have to suppliment in a better render engine (not a problem with Blender). Carrara is simplier to use and hencefore often faster to model, texture, and work with. Carrara's "extras" like the terrain builder, tree modeler and other tools makes it quicker to get some things done. Carrara's SM makes machical objects easy to build, whereas you'll have to model more like Hexagon's tools via hotkeys in Blender.
This ease of use and speed of use is why many people in this and other forums continue with Carrara. Cinema users have stated that while Cinema is more powerful (and extremely expensive in comparison) they like and prefer Carrara. Haven't heard too much from XSI and Carrara, but for the last year or so, they've been competiting on the same price point and XSI is used in the film/entertainment industry. 3D Max and Maya, from personal experience, is great for animation and blows away most other feature sets from other programs, but they are also the most expensive. Lightwave can be complicated, and while used in the industry, it is not the quickiest solution... they need some serious work-flow enhancements.
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I'm sure Blender will eventually come out with 2.40. It's been 4 months from the original posting of this message,
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