Row Counts for all Tables in a database:
select DB_NAME()+'.'+C.NAME+'.'+A.Name as [TableName],B.TotalRows from sys.objects A Inner Join
(Select sum(rows) as TotalRows,object_ID from sys.partitions group by object_Id) b on A.object_id=B.object_id
INNER JOIN Sys.schemas C on C.SCHEMA_ID=A.schema_id
where type= 'U' order by C.Name,A.Name
Note: I have seen some people mention online that the only accurate way of finding the row count is by doing count on the actual table itself.I could not verify this but may be something to keep in mind.