You should read the FairTax bill to see that it calls for the repeal of the 16th amendment AND eliminates the IRS (it defunds it as well as legislating it out of existence) and it also requires the destruction of the income tax records.
The FairTax is a tax bill, not a constitutional amendment bill. The requirements of the two are quite different. Also the 16th cannot be repealed without having a functioning tax law in place or ther would be no funds to run the govenment (maybe not a bad idea:-)).
Once the FairTax is law the repeal effort can really begin to move. As a matter of fact, Congress could RIGHT NOW vote a sales tax in addition to an income tax ... SHH! - don't tell them. The FairTaxx would actually work to protect us from having both at once.
Read the bill and you'll see.
The IRS is power to politicians, to have it gone means a lot of their influence goes as well.