Service that displays how many inputs/outputs there are in the blockchain? Ideally, I am looking for a service like http://statoshi.info/, but one that displays the real-time number of inputs and outputs in the blockchain. 

Note that I am not looking for information on the UTXO set, but the set of all inputs and outputs that are in the main bitcoin blockchain.

This is a useful statistic for developers because it has implications for the data storage requirements of parsing the blockchain and storing data per input/output.
http://webbtc.com/stats

This website displays statistics about its own output database, though it should be very rare that any developer need to maintain an index in this way. Most people will only need to interact with their own, unspent outputs rather than the entire history of the mostly unrelated chain.