Are all fluorophores dipoles? Lately I'm reading about surface enhanced fluorescence. In many articles I can see that fluorophores are called "dipoles". Is it because that they can be modelled by a vibrating electric dipole? Or maybe they are all chemical dipoles?
 A: In short, no, not all fluorophores are dipoles in the permanent dipole sense. As a counterexample, anthracene has zero permanent dipole moment, but fluoresces blue under UV illumination.
The reason why many fluorescent molecules are called "dipoles" is because electric dipole transitions between quantum states occur due to nonzero values of the transition dipole element between those states. So while anthracene's ground state has zero permanent electric dipole, the transition dipole element between the ground state and the relevant excited state turns out to be nonzero.
A: Another counter-example with the same comments as in DumpsterDoofus's answer is uranium, usually present in fluorescent minerals or uranium glasses such as the art glasses annagelb and annagrün as the uranyl ion. Similar uranium ions give "yellowcake" its intense yellow colour. 
This fluorophore is particularly important historically, because it was the study of its fluorescence that led Henri Bequerel to the discovery of radioactivity. Bequerel was struggling to explain the fluorophore's inexplicably long-lived glow: now we know that the uranium's radioactivity was driving the fluorescence after decay of UV-excited fluorophores had died away in his investigations.
One often calls the uranium fluorescence a "phosphorescence", because the release of light comes from the decay of lowest triplet excited state to the singlet ground state. Simple quantum mechanics shows that the coupling between these two is nought; in practice, there is very small coupling owing to the ion's interaction with its environment. Presumably the long lifetime made it quite hard for Bequerel to prove where the fluorescence was coming from. 
The ion has a broadband fluorescence between 500nm to 550nm, as shown below for uranyl absorbed into glass below, so it glows greenish yellow.

It is excited by UV light, as shown in the spectrum below

which figure I have taken from:
Nicholas A. Smith, Gary S. Cerefice, Kenneth R. Czerwinski, "Fluorescence and absorbance spectroscopy of the uranyl ion in nitric acid for process monitoring applications", J. Radioanal. Nucl. Chem. (2013) 295:1553–1560
