Over several decades I have accumulated a HUGE library of instructional books/tapes/dvds/CDs, etc. IMO, when it comes to actually learning-the-instrument and how to play it - GT is the way to go. Once you get to the point you have at least a basic command of technique and theory and more of your playtime is devoted to playing songs than practicing scales/techniques, etc. there are quite a few good/helpful/interesting books out there.

For example I have a book/cd pkg dedicated to Reggae. It's done well and I have absolutely benefited from it. I re-visit it at least once-a-year. Most significantly I have a LOT of the "Play-a-Long" type books that feature specific genres or artists with demo track and "minus-one" track. The tab is usually pretty good and learning a song and then playing it up-to-tempo and in-time (band setting) is invaluable because that is what I struggle with the most. It also encourages me to learn songs completely, start-to-finish, rather than just parts or favorite licks. GT of course +1's this by providing a visual of a muted guitar playing in the "jam-along" sections.... but the song selection is limited compared to available play-a-long books... and they're CHEAP! Hundreds of them on Amazon for $10-$15 ea.

As far as JamPlay... I am following closely to see if/when they run a $$ special on signing up for both Guitar AND Bass. I "tinker" with bass but I feel like I could up my potential for playing with others by being able to answer "yes" to the most frequent question I'm asked when I'm trying to network in the musicians community... Me: "Hi, I play guitar" ... Them: "Cool, can you play bass?"

Try a couple of the "play-a-long" book/CDs and force yourself to play the entire song, in time, and up to tempo ... I find it pretty satisfying.

Take Care