Despite Wikipedia's desire to be a Cleanie endeavor (background on Scruffies vs Cleanies here), it is inherently Scruffy. I am amused, bemused, and then slightly annoyed at reading about "The battle for Wikipedia's soul" in the Economist last month (article here). There are certain ideals to which Wikipedia can rightly aspire: accuracy, concise representation of existing knowledge, and so forth. Deciding which knowledge is "worthy of" inclusion when housed in a medium of infinite capacity should not be one of them.
There is nothing more Scruffy than harnessing the power of everyone (known as crowd-sourcing, a term even newer than Wikipedia itself). Trying to get all hissy (sorry, Cleanie) about what knowledge is "serious" is patronising at best, stultifying in any event, and censorious at worst.
Just because Scruffy is the "opposite" of Cleany does not mean Scruffiness is the same as dirtier or less ideal. Scruffiness, in this case, is the idea that putting things together in a haphazard way, and iterating when needed, often leads to better results than "over-thinking" an initiative and trying to design it perfectly from first principles before commencing. Recent research shows that people with tidy desks spend more time looking for stuff than people with mess desks - I have a messy desk so I can't find the reference right now, but trust me, it's here somewhere!