Are there Nirnroots in Skyrim?
Solution 1:
Yes, there will be Nirnroots in Skyrim:
This image is from the G4TV Skyrim demo. You can also see Nirnroot in the Skyrim Trailer.
You can find information about its alchemical properties, location, quests and lore on the Elder Scrolls Wiki Nirnroot page.
Solution 2:
Yes they are in game and you can still collect them(Listen for that familiar Nirnroot humming). You can also find a farm that grows it!