Zemanta, a Slovenian company that uses semantic technology to assist bloggers and other online publishers, has unveiled a set of new features that should make it far more useful to professional users.

Available as a browser extension or direct plugin for publishing platforms like WordPress, Zemanta provides suggestions for links, pictures and images as you write. This evening, it’s adding the ability to customize and add preferences to the content it suggests.

The plugin as it already exists is useful tool for bloggers because, after writing, finding associated content to add to posts and articles is the most time-consuming aspect of online publishing. Zemanta taps into image sources (like Flickr) or content (like articles on related news) to vastly speed the hunt-and-peck process of adding links, images and tags.

But those features weren’t particularly useful to pro bloggers or publishers, because each has their own in-house requirements. VentureBeat, for example, has plenty of past coverage to tap into; if I want to mention Zemanta’s launch, I want the link to point to our own article, not an article somewhere else. Other publications may have in-house photo databases or other sources they need to use.

The company is working on ways to allow as much customization as possible, and will likely charge publishers a subscription fee for it. For Zemanta’s free tool, co-founder Bostjan Spetic says that there will be a different monetization strategy. One possibility is suggesting affiliate products for posts, so that if you wrote on your personal blog about your Canon SLR, Zemanta might provide an affiliate sales link.

Also slated for future release is an API, which Spetic says test developers are comparing to OpenCalais, financial publishing giant ThompsonReuter’s in-house semantic project.

Zemanta also just took more than $650,000 in seed funding (although some different amounts were reported at the time). It has taken $1.5 million to date, and Spetic says the company will be looking for a full venture round by the middle of next year.