What is "Fibonacci" about the Fibonacci LFSR?
If I read right, Fibonacci LFSR means that it depends on its two last states, but from the example in Wikipedia it doesn't look like two states are taken in consideration (ie. XORing the taps in the current state, shifting and inputing the left bit..). 
What am I missing?
It depends where the logarithm is. If it is just a factor, then it doesn't make a difference, because big-O or $\theta$ allows you to multiply by any constant. 

If you take $O(2^{\log n})$ then the base is important. In base 2 you would have just $O(n)$, in base 10 it's about $O(n^{0.3010})$. 
