"Can I safely asume that links between subsites on a subdirectories based multisite will be treated as internal links within a single site by Google?"

At best.

Unless they're otherwise straight-up  professional links with zero spam intention, I wouldn't use them.

Morris,

As strong component of a linking strategy, the heyday of press releases has come and gone but press releases are still valuable.  They're valuable in the sense that they've always been valuable--as a means to reach a targeted audience with a creative message about a topic that will be of interest to them.

Press releases are an active engagement tactic, in that you research what publishers you want to target, you craft a message that is going to catch their attention, you send it via a channel you expect them to be listening on, and then you expect to engage and develop relationships with your target publishers.  Unfortunately, many people today think of the press release as sort of a passive tool--you write something that fits into the template you pay your money then you hit submit and you wait for all the links to come in.

Don't think of press releases as a way to get links, think of them as tools in building new relationships.

Sorry to all, I shouldn't have replied in that manor.

Thanks for the info.

As Matt said, boilerplate stuff is a tossup but your about page should be rankable for some unique facet of your business and for that reason, I'd be sure to 301 (if the pages are different) or canonicalize (if the page content is the same) to your preferred version.

Don't  worry about all that  header stuff; Google doesn't (very much).

Are your most important words in the topmost locations in your html? That's what you want to care about. Are you  using them in your initial headings? Are you using them in your initial  sentences and paragraphs?

But remember, it's not just about "keywords" it's about supporting/complimentary vocabulary. If you're just throwing your keyword into copy that is otherwise fluff ( contains little topical concepts and terms), you're not going to beat out other sites that do.

If you made the .nl site the same as the .com com site, you could also cross-domain rel=canonical each page over to the .com site, which would leave visitors on the .nl site but assign all value over to the .com.  As Ash said though, putting unique content--either Dutch or English--might me your most effective option.  It may be even more effective if you host it in the Netherlands, too.