This is a toolbox that records Get Count results in an output table. The model is provided with a batch tool that can be used to run the count on all the feature classes in a workspace. It is another demonstration that a little bit of Python (used in the Calculate Value tool) can make ModelBuilder a lot more useful!
Update: added a second tool to run counts on standalone tables instead of feature class tables.
To use, open the model tool (Run Row Counts or Run Row Counts on Tables), provide workspace, wildcard, format. The tool will create one output count table for each input, these can be merged with the Merge tool and converted to Excel using the Excel To Table tool.