Look, I know it's redundant, but "Eruption" is still the best solo ever. Here's why:
It's over 30 years old and people, not just me, but a lot of people STILL marvel over it. It was SO cutting edge at the time, that people didn't know how to comprehend or interpret it. That's epic, when something has that kind of staying power.
I know the argument can be made that EVH hasn't done anything REALLY cutting in 15 years or so, but the reason for that is that he IS the cutting edge. People are still playing catch up. He did pinch harmonics and pentatonic scales when Zakk Wylde was still shittin yellow in his pampers (and that's not a knock on ZW - see end of post).
Even if someone matches the raw cutting edge nature of "Eruption" it will still never measure up because "Eruption" came first.
With time, we've become immune to its greatness because it's always there sitting on the pinnacle. We've taken it for granted after all this time. But if you can go back and listen to it, completely clear your mind and imagine you are listening to it for the first time, you'll once again find yourself going, "Woooooow, that's REALLY smokin'. Dude's absoLUTEly shreddin the frets." It's really that good. Go back and have a listen.
Now, for my money, one of the best if not the best in song solos is "No More Tears" by Zakk Wylde, who I think is the greatest living geetar player right along with EVH.