That is the second vote for INTJ, although I bet the first one was at least partially due to the misconception that it was my voice. I think the actual owner's current self-assessment is different, however. I imagine he (or she!) finds these results interesting.
I had doubts as to how successful the anonymity aspect of this thread could be given that many people have already posted samples in other threads or spoken on Vent, but apparently it works quite well.
What makes you say ETP? The content or the style of the sample?
The style, which was quite direct and lively, the speech sounded confident and clear -That's why I think extrovert, rather than introvert. The melody goes through several changes, but without emotional undertone (T>F), I am not sure if the melody changes are there because of the enthusiasm, or something else, because the quality of the recording is not really good. So it's hard to say whether it's more steady S way of speach, or if it is more inuitive enthusiastic way. Based on the rythmics, I'd say N, because the speach is quite arrythmical and it seems to be pretty fast, not really organised, or prepeared P>J.
Is it cheating to consider the choice of reading material in addition to the voice quality itself? Most of the Asimov fans I've known have been INTs. To be different from the previous two votes I'll go with INTP.