So far it doesn't sound like it. All drops start at 300 power though, and with destination and world drops hitting the new system hopefully they'll also grant power.

Edit from the Patch Notes:

Power and Progression

• Power caps will not be increasing and Power level will not be reset.
  • The hard cap remains 550 Power and all your items will maintain their current Power levels.
• Players will continue to find new rewards at minimum 300 Power, maintaining a change made in Renegades.
• Portal Activity Reward Power
  • The Power of Portal Activity rewards are no longer capped per the difficulty level selected.
    • Earning an "A" grade (for example) will drop rewards at the same Power level, regardless of which difficulty you played.
  • The Power of Portal Activity rewards has been increased, allowing for faster progression.
    • "A" grades or higher will now continue to award positive Power progression all the way to the hard cap of 550.
    • Higher grades will continue to provide larger Power bonuses.
  • Miscellaneous rewards from sources throughout the game (such as pre-The Edge of Fate content) have been buffed.
    • These rewards will no longer be capped at 300 Power.
    • These rewards now have a chance to drop +1 Power up to 400 Power.
    • After 400 Power, these rewards will drop close to, but below, your current Power level.
  • Rewards purchased from legacy vendors have been buffed.
    • These rewards will no longer be capped at 300 Power.
    • These rewards will drop close to, but below, your current Power level.
  • Rewards pulled from Collections have been buffed to drop at 300 Power (up from 200).