Well, at first listen, in terms of the mp3, not only is he using strictly pentatonic in a super lame fashion, half of the time it sounds way too rushed, and the soloists's timing is very bad.
The tone, in my opinion is also quite lacking. I'm not the hugest fan of the blues, as I find a large amount of their players are close minded and, once again, use strictly Pentatonic scales and their phrasing is very predictable. Also, in the Mp3, the soloist doesn't seem to use any techniques aside from bending and slurs.
In my opinion, what makes a great guitar player is somebody who can find their own style. Especially nowadays, with as many possibilities to learn, and to pick up what with backing tracks, things like that, a person can learn quite quickly how to play very well.
BUT, technical ability, in my opinion, does not necessarily make a good guitar player.
For instance, I had a show about two or three weeks ago, and one of the bands that opened for us had this guitar player, and he seemed to know just about everything. Honestly, this kid could shred. Before his band went on, we talked about tons of stuff, and he knew his shit, and, once again, he could shred.
BUT, when his band went on stage, the songs that his band had written were really bland, and he really looked like somebody ho didn't know what he was doing.
A Lot of people focus on being able to shred, or being able to solo like none other, but honestly just because you can shred somebody's face off, doesn't give you an ounce of credibility, in my opinion. I have met many guitar players who, if you asked them to solo, wouldn't be able to do much of anything, but put them in an environment where they are writing and interacting with other players, and they shine and write parts that are mind blowing.
BUT, what I think makes a good soloist, is somebody who has a very strong vibrato, plays notes with some sort of conviction/power, uses advanced techniques, and plays cleanly.
But that's just my opinion, I dont necessarily have a whole lot of credibility eitherlol

Stuff like scale choice and tone are subjective stuff, where one man's meat is another man's poison. I think the timing and phrasing prevents the solo from being good even though the player obviously has the technical ability to create a decent blues based solo. Although I have varying opinions on who I think are 'enjoyable' players to listen to and what makes a 'great' player, I think EVERY 'good' guitar player must have a halfway decent concept of timing and phrasing and pitch if you're going to use stringbending. Kurt Cobain is a guitarist who gets flamed in almost every guitar message board for being a crappy guitarist, but he played his solos relatively in time and had a decent sense of phrasing. I also think if you played the general populace a copy of this MP3 and also Jimi's original version of Hey Joe, they would not be able to tell which one was better.