In a fresh installation the 'Home Page' seems to make use of the custom 'Heading' field whilst the 'News' channel makes use of the 'Title' field.
What is the advantage of using the 'Heading' field over the 'Title' field?
The short answer is, we should probably update that :)
The long answer is:
The homepage is a “Single” section, and originally, Singles couldn’t have dynamic Title fields like Channel and Structure sections; their titles were static, based on the section’s name. So in this case, that Homepage entry’s title was “Homepage”, and the only way to change that would have been to go into the section’s settings and change its name from there. So, back then, if you wanted to give a Single a “Title”-esque field, it had to be a custom one. Which is what that Heading field is – a custom Plain Text field.
As of Craft 2.2, however, Singles can now have dynamic Title fields. So at that point we should have updated the default fields to stop giving that Homepage section a custom Heading field.
Hope that clears things up a bit. I’ll go ahead and make that change for the next release.