Recently google has really downplayed the importance of exact match domain names. If the domain name is newly registered it probably hasn't earned any links yet, and therefore wouldn't pass any SEO value.

Copyright notices are really just a signal for the users, and to say "don't steal our stuff" in somewhat of a non-forceful way. People can generate the year automatically, but sometimes they just forget to include it.

Is it a big deal to have an older date? Probably not. Google has a number of other ways they could check a page's freshness aside from a completely arbitrary copyright date.

An interesting note about copyright, you don't really have to display a copyright notice in the first place. As soon as you create something, it's already considered "copyrighted."

The most common services we see through addthis are actually facebook and email.

zharriet has a good point. You could really do the same thing with a few icons and skip the javascript.