Review of Gephi powered by the Slant community.
Free and open source software written in Java for visualization and exploration of graphs and networks.
SpecsUpdate
PlatformsWindows, Linux, Mac
Ranked in these QuestionsQuestion Ranking
Pros
Pro Import of graphs
Supports GEXF, GDF, GML, GraphML, Pajek NET, GraphViz DOT, CSV, UCINET DL, Tulip TPL, Netdraw VNA and Spreadsheet.
Pro Well documented
Lot's of documentation and tutorials available.