The IEEE Symposium on Large Data Analysis and Visualization will be co-located with VisWeek again this year, in October. Papers are due May 15 (abstracts on May 8), and more info is at http://www.ldav.org. The Symposium focuses on techniques for the collection, analysis, manipulation or visualization of large-scale data including topics such as novel, extreme or innovative methods for understanding and interacting with data; data mining and machine learning techniques for large data analysis; topics in cognitive issues specific to manipulating data. Dan Best presented here a couple years ago, so you could ask him what it's like if you have questions.