Scientists are silly sometimes. For example, there is no standard way to figure out what a given researcher has published, nor to find out which papers appeared at a given conference and a given year. DBLP is one tool that tries to solve this problem for Computer Science. It is far from perfect, but its coverage is sometimes considered good enough.
For better or for worse, the reviewers of my last grant applications skipped my carefully crafted c.v. and jumped right into my DBLP publication list. (Remind me to no longer submit publication lists with my grant proposals and just write “see DBLP”.) I must admit that I routinely use DBLP to quickly determine what are the research interests of a given individual, or to find interesting conferences or journals.
One limitation of the DBLP is that its search engine is just not very powerful. Things are improving thanks to Faceted DBLP. The search function itself is not more powerful, but you get aggregated statistics on individuals and conferences. Want to know whether a given conference grows in number of papers presented per year? Want to know the most prolific author at a given conference over the years? These queries are now trivial.