But Thunderbird proves mindcrime's point - even though Mozilla-the-company has decided that developing Thunderbird is no longer aligned with their interests, community-driven development will continue, because it's open source. Yes, development will be diminished, but it won't die outright like Sparrow or other closed-source software would.

For most consumers it's the same. I'd rather pay someone a few dollars than maintain Thunderbird myself (for example) and most people realistically do not have the option of maintaining it themselves.

On the other hand I use a lot of OSS on servers and in the past on my workstations, and have modified them and fixed bugs and such. There are definite advantages but this particular one is not that useful on a large scale.