This question arose from an earlier one and the MO user's useful answers there: http://mathoverflow.net/questions/80710/what-are-the-values-of-the-derivative-of-riemanns-zeta-function-at-the-known-non/80783#80783 (which is not a prerequisite for this version). 
As usual, let $\rho=\beta+i\gamma$ denote the non-trivial zeros of $\zeta(s)$. Essentially, the question is this: 

How are the numbers $e^{i\phi(\rho)}=\lim_{s\rightarrow\rho}\zeta(s)/\overline{\zeta(s)}$ distributed in $\mathbb{T}$?

Of course $\phi\in\mathbb{R}$ and the limit could be replaced by quotients of derivatives if we knew the order of the zeros (in which case $\phi$ is just twice their argument there), but I don't think it is necessary to know that any way. Moreover, I think the answer is independent of RH. My reasoning is as follows.

For $x\in\mathbb{R}$, one may consider the mean-value:
    $$M(x)=\lim_{T\rightarrow\infty}\frac{1}{N(T)}\sum_{0 <\gamma < T}e^{i\phi(\rho)x}.$$
Let $t>0$ and $\theta(t)$ denote the Riemann-Siegel theta-function. Firstly, by separating the sums over zeros on and off the line $\beta=1/2$ and, secondly, by the Bohr-Landau theorem (that the number of zeros with $\beta>1/2$ is $O(T)$), one gets
    $$M(x)=\lim_{T\rightarrow\infty}\frac{1}{N(T)}\left(\sum_{0 <\gamma < T  :\beta=1/2}e^{i\phi(\rho)x}+O\left(T\right)\right)$$ 
    $$=\lim_{T\rightarrow\infty}\frac{\pi}{\theta(T)}\sum_{0 <\gamma < T  :\beta=1/2}e^{-i2\theta(\gamma)x}.$$ 

If my reasoning is correct, $M(1)=0$ is equivalent to $e^{i\phi(\rho)}$ being dense in $\mathbb{T}$, and $M(n)=0$, $n\in\mathbb{N}$, to them being uniformly distributed. Any advice, insights and corrections would be most welcome.

EDIT 1: the arguments are $2\theta x$- corrected.

EDIT 2: $O(T)$ inside the bracket- corrected.