Libet himself concluded that our awareness of decision making appears to be an illusion, that consciousness is "out of the loop".
This appears to be different than denying free will. We are conscious of the need to make a decision but we are not necessarily conscious of how that decision is made.
The neuroscientist Vilayanur Ramachandran, gives an interesting take on Libet's results:
Given that we have on the order of 30 billion neurons in the neocortex, there is always a lot going on there, and we are consciously aware of very little of it. Decisions, big and little, are constantly being processed by the neocortex, and proposed solutions bubble up to our conscious awareness.
Ramachandran then goes on to suggest that, rather than free will, we should be talking about "free won't" - i.e., the power to reject solutions proposed by the nonconscious parts of the neocortex.
Daniel Dennett commented on Libet's result:
The action is originally precipitated in some part of the brain, and off fly the signals to our muscles, pausing en route to tell you, the conscious agent, what is going on (but like all good officials, letting you, the bumbling president, maintain the illusion that you stared it all).
One might wonder: If the subject is unaware of when s/he is aware of making a decisions, then who is? But the point is well taken - what we are conscious of is far from clear.
(Both of the quotes I have given are taken indirectly from Ray Kurzweil's book, How to Create a Mind.)
Something that has always intrigued me, and that we have all experienced, is the ability to access our memory, and even our reasoning, without consciously thinking about it. We may be asked a question which we should know the answer to but we cannot seem to form the answer, no matter how hard we try. We might say "I'll have to think about that", although we give it no further conscious thought. Some time later, perhaps days later, the answer will suddenly pop into ones mind. We have submitted our will to our subconscious, where it has been subsumed (intact) and acted upon. Why should the decision making undertaken by the subconscious be any different (less free) than that of the conscious.
EDIT 16 Aug 15
I have (or more precisedly, Kurzweil has) incorrectly attributed the notion of free-won't to Ramachandran. According to Susan Blackmore, it was Libet himself who suggested this alternative.