The phrase "as its default" is correct and usable in written English.
It can be used to indicate a standard or pre-set option that is automatically selected unless changed by the user.
Example: "The software saves all files as its default in the .docx format unless specified otherwise."
Alternatives: "by default" or "as the standard option".
After all, the main reason Nambu is giving for folding Tr.im is that it can't compete against Bit.ly when Twitter is actively promoting and using it as its default link shortener.
It is not clear how the new feature will affect bit.ly, the third-party link shortener Twitter currently uses as its default, but it sounds like that may change soon.
A 69p app for those hankering after Street View now that Apple has done away with it by dropping Google as its default map provider.
Privacy-focused search engine DuckDuckGo did something unexpected recently - it brought in Apple Maps as its default mapping partner.
Similarly, Dr. Tevanian said that while Apple offered both the Microsoft and Netscape browsers, it had originally chosen Netscape as its default browser.
The fonts we use are illustrative of the times we live in in 2007, Microsoft did away with Times New Roman as its default typeface for Word, replacing it with Calibri, a more rounded, sans-serif font.
Although the Federal Reserve had helped bail out Bear Stearns — and was within days of bailing out the giant insurer American International Group — it could not help Lehman, even as its default threatened to wreak havoc on financial markets.
The Maxx HD also has the Google goodies that were banished from the iPhone, like Google Maps and Google Talk, and it uses the speedy Google Chrome as its default browser.
Up until now it seemed like Mozilla was going to be using Geode, a plugin it first annouced back in October, as its default location provider.
This morning, Mail.ru confirmed (in Russian) that it will be replacing Yandex with Google as its default search provider starting January 2010.
As its default setting, Microsoft Outlook has "receipt requests" turned off.
