Adobe is continuing the trend they started with the Flex SDK and will provide the Apollo SDK free of charge.
This is an excerpt from the Apollo for Flex Developers Pocketguide:
The Apollo SDK provides a number of free command-line tools that make it possible to test, debug, and package Apollo application swith virtually any web development and design tool. [...] While Adobe will be adding support to its own web development and design tools for authoring Apollo content, they are not required. Using the Apollo command-line tools, you can create an Apollo application with any web development tool. You can use the same web development and design tools that you are already using today.
This is really good news, and probably a very good strategy on Adobe’s part. Instead of shying away from buying a full development environment for hundreds of dollars, potential new developers can try out the platform for free and without restriction.
I for one have changed my view of Adobe/Macromedia as a company over the last year, from mildly sceptical to very entusiastic.