With AppEngine at Google, MongoDB at Disqus, Cassandra at Facebook and Redis at Github you can definitely say that SQL databases are one of many options available today and don't dominate like they did 5 years ago.
SQL is being replaced in niches that strain its model. elsewhere, it remains steadfast.
I think nobody expects SQL's "market share" to fall to low levels, especially with noSQL requiring much deeper understanding of the data and it's planned use. NoSQL practically operates on a lower layer than SQL does.
Still, it's nice to see people thinking about data storage choices and not going blindly to MySQL/Oracle/etc!