Type "/insight" to open the options panel. Most PlayerFrame options can also be toggled with keybindings.
Insight displays player health, mana/energy/rage, charges (when applicable), and exp info. Also colors player name when auto-attack is enabled, and colors health bar based on health percentage. Health and mana/energy/rage can be displayed as a percentile. it also allows display of health and mana values at your target's portrait.
The /tnl command sends your TNL (to next level) info to say, party, raid or guild chat, or just displays it for only you, or whispers it to a friend. Type /tnl help for more info.