With the second major redesign, the Twitter web site added inline previews for images and video – it should help turn the site more into a destination for media consumption rather than a simple referral to original content. I noticed a couple of days ago that the rich previews are now generated for some links as well, namely those pointing to the domain wordpress.com; just do a Twitter search and click on the link ‘View media’ under the individual tweets.
The previews include snippets from the blog posts – the first paragraphs by the looks of it – and a picture – again, likely the first. For now the previews appear only in the stream, not on the individual pages for tweets. They look positively – dare I say it? – Facebook-like, especially now that open tweets also display interactions (replies, favorites, retweets) underneath! I would prefer a slightly smaller picture, right now they tend to fill up the entire vertical space on the screen, which feels out of place for a service known for brevity. This sneak-peak should help build user trust that the links don’t point to some malicious site and that the page is worth visiting. I didn't discover other domains with similar previews, but it’s reasonable to assume that it will be extended in time for more sites – needless to say, no Twitter client supports this feature as of now, not even the in-house-maintained TweetDeck.