PLoS recently launched its article-level metrics program for all of its journals. At O'Really, Duncan Hull takes a look at the data from the top 10 papers. He says that "this is novel, interesting and potentially useful data, not currently made publicly available by other publishers."
DrdrA at Blue Lab Coats is also intrigued. "I love this feature because it reflects reality to the level of readership of a given article better and more immediately than the traditional pre-electronic media age measures such as citation rate or total citation number could," she writes.
Hull also warns that "analysing this data is not straightforward" and that "popularity and importance are not the same thing."