There are a lot of german sites, which arent mentioned in this list, but okay. To cut a long story short: its not a top 100 list, its a list of "web apps with the most bookmarks". Nothing more.

Back to topic: StudiVZ, Xing, Spreadshirt, Mister Wong and Plazes are international. The most of the others in the list are more "fun projects" than anything else. Take a look at "Seitwert", "popurius", "logo creator" and so on.

Outside the US where funding is harder to come by, years of no revenue and a visionary push for huge traffic (wherein valuation pay-day is finally hit) is that much harder. Perhaps they can monetize earlier locally, albeit at a smaller valuation.

But for those sites that are generic, and could easily have global application, are the digerati too knowledgable and prefer to stick with the high profile alternatives?

Philipp's comment kinda misses the point because the list does not claim to represent anything else:

"This list is based on counting the number of bookmarks of about 1,000 services from Germany we are aware of at the bookmarking service del.icio.us. While it is hard to find significant metrics for measuring the popularity of sites, it’s even harder to access reliable data for any metric for all sites. Going with del.icio.us is straightforward, but not necessarily an indicator for a large number of active users, traffic or economic potential.

"Sites which are available in English do have a competitive advantage at del.icio.us compared to sites which are in German only. Sites which have been around for a while have an advantage compared to services which launched this year or a few weeks ago. A few of the most popular sites in this list are useful and focused but rather smallish tools which attracted a lot of bookmarks because they made it on del.icio.us’ hotlist. The list misses a few popular or interesting services, but overall the heuristics works fine."

Blame me for being a bit overambitious with the title, but please take this list lightly and for what it is. It is a bit unfortunate that useful but small tools occupy the top spots though, maybe I should have filtered by language.

A datapoint regarding your observation that there are not that many sites which directly strive to go global: based on the sample of 1,000 sites only 5% come in English only (e.g. Marshall covered lifestrea.ms recently, there are a few interesting sites emerging around lifestreams / decentralized social networks here), I don't have detailed numbers on how many provide localizations, but make it another 10% to the max. The rest happily serves the Germany market only.

I don't want to fill this copycat argument but a lot of sites from Germany really just adapt and reinterpret an existing idea to the local market (e.g. we've got 15 Twitter clones, but there is a German aequivalent to basically every service) and often it makes perfect sense to harvest a smaller market which still is big enough (e.g. bad Facebook clone StudiVZ just topped 5 billion PIs in a month) and not bother competing where nothing can be won anyways anymore. But we also have seen that once a site has established itself in Germany it then expands internationally and strikes back a few times (e.g. Qype, Mister Wong, Verwandt, Sevenload, StudiVZ), sometimes successfully so, sometimes not so much.

It is one of the most promising community and rating projects as far as politics as well as web-democracy is concerned.
Currently, the site exists only in German but the team already plans to internationalize.