decreasing number of definitions

Here Avast! is at 100907-1 virus definitions version with 2,519,269 definitions - but is it my imagination or has the number of definitions decreased recently ?

http://blog.avast.com/2010/09/06/spring-cleaning-in-our-virus-database/

thanks igor, I knew there must be an explanation and an answer somewhere - I thought it was probably that.

I have never felt the need to track the number of signatures, as the most important bit is the wording below the figures.

True !