Not entirely unexpected. When Chelsea appealed a similar ban (which they won), they were still forced to sit out a transfer window whilst the appeal took place.
Below is the official statement from the FIFA:
The club FC Barcelona has lodged an appeal before the FIFA Appeal Committee against the decision of the FIFA Disciplinary Committee that sanctioned the club for breaches relating to the international transfer and registration of players under the age of 18. Together with the appeal, the club requested that its appeal be granted suspensive effect.
In this respect, the chairman of the FIFA Appeal Committee, Larry Mussenden, took into consideration the sanctions imposed against the club, the complexity of the matter, the start date of the next registration period – 1 July 2014 – and the fact that the FIFA Appeal Committee does not seem in a position to take a decision on the main issue early enough so that an eventual appeal of the club against its decision before the Court of Arbitration for Sport would still be decided before the beginning of the next registration period. Consequently, the chairman of the FIFA Appeal Committee considered that the appeal lodged by the club is to be granted suspensive effect.
In view of the foregoing, the chairman of the FIFA Appeal Committee assures that proper and adequate appeal proceedings will take place and, at the same time, that all rights of the club will be respected.