You can now access the Coinprism colored coin blockchain explorer at coinprism.info.
It has all the functions of any blockchain explorer (shows any transaction or block in the blockchain), but it also shows colored coins transactions.
Here is the homepage, from which you can search for addresses, transactions, blocks or assets.
You can see information about any bitcoin address:
An asset directory is also available at www.coinprism.info/assets, where you can find the top colored coin assets:
Let us know if you have any feedback or question!