Wine is forbidden for a Muslim here on earth:
See also Sura 2:219.
On the other hand in Paradise are rivers of wine:
Surely the pious will be in bliss ...
their thirst will be slaked with pure wine sealed.
-- Sura 83:22,25
Is wine good or bad? Are we forbidden on earth something that is truly good? Or in Paradise are we not only allowed it, but even provided in overflowing measures (rivers of ...) something that is so bad that it is called "Satan's handiwork"?
Some Muslims attempt to explain away the discrepancy by appealing to the following passage:
Save single-minded slaves of Allah; For them there is a known provision, Fruits. And they will be honoured In the Gardens of delight, On couches facing one another; A cup from a gushing spring is brought round for them, White, delicious to the drinkers, Wherein there is no headache nor are they made mad thereby. And with them are those of modest gaze, with lovely eyes, (Pure) as they were hidden eggs (of the ostrich). S. 37:40-49 Pickthall
The heavenly wine, it is claimed, which believers will drink will not cause headaches or madness, thereby justifying Allah's decision to permit it in paradise.
The main problem with citing this is that the passage nowhere identifies this drink as wine. It does not even mention either the word wine or strong drinks/intoxicants. It simply says that believers will drink from a cup something which is white in color which does not cause headiness. If anything, one can make an argument that this drink is actually milk. After all, the Quran does mention the fact that believers will be given rivers of milk, and milk is indeed white:
A similitude of the Garden which those who keep their duty (to Allah) are promised: Therein are rivers of water unpolluted, and rivers of milk whereof the flavour changeth not, and rivers of wine delicious to the drinkers, and rivers of clear-run honey; therein for them is every kind of fruit, with pardon from their Lord. (Are those who enjoy all this) like those who are immortal in the Fire and are given boiling water to drink so that it teareth their bowels? S. 47:15 Pickthall
Here is the other text which Muslims quote to prove that the wine in paradise will be different:
with goblets, and ewers, and a cup from a spring (no brows throbbing, no intoxication) S. 56:18-19 Arberry
Again, the reference nowhere mentions wine and can be referring to the other drinks which the Quran says will be given to believers, i.e. honey, milk, water etc. In fact, the Sura goes on to mention the flowing waters which believers will have:
By water flowing constantly, S. 56:31 Hilali-Khan
Thus, one can legitimately say that the spring which the Quran says will not cause throbbing or intoxication are these very waters. This becomes even more apparent when we realize that the Quran mentions the fruits that the believers will eat from right after the Quran refers to the spring and flowing waters:
and such fruits as they shall choose, S. 56:20 Arberry
And fruit in plenty, S. 56:32 Hilali-Khan
In light of the foregoing, it seems pretty certain from the context that the drink which the Quran says doesn't cause intoxication is in fact the very flowing waters that are mentioned later on in the chapter.
Moreover, one can even argue that the reason these passages emphasize that these particular drinks don't cause headiness or intoxication is to distinguish them from the wine which believers will have access to when in paradise. In other words, the qualification presupposes that these drinks are different from the wine which believers will be drinking since, unlike wine, these specific drinks don't cause madness or headaches. Putting it in another way, these texts are not identifying these drinks as wine, but are actually contrasting them to wine by highlighting the point that they don't have the common affects associated with intoxicants.
Further reading: The Quranic Teaching on Wine and Strong Drink
Contradictions in the Qur'an
Answering Islam Home Page