It might be a decent learning aid but the song list is tiny and there doesn't seem like there is any ability to tab your own and upload for other people. Then to get more you have to pay for each song and lets face it there are many other guitar tab programs out there that let you download tab for free, this all seems a bit cynical, especially when you are already paying £45-60 for the base package. Very poor.
The song list is as big as the original game, over 50 songs. I'll be the first to admit that I don't think the song list is as good as the original's, but it's not bad either. Also, if you have the original game disc, 2014 will be backwards compatible. I'm not sure how it'll work yet but they're saying that you'll be able to use that track list as well which ups the ante to over 100 songs. Plus, any DLC you have will work.
I also really like the improvements they've made. They've added a bunch of new guitarcade games which I really liked (they help a lot, trust me) and session mode could be worth the $60 pricetag alone. It's a guided jam session that gives you dynamic backing tracks that conform to your playing style. This is the type of thing you can never do on your own.
And trust me, tabs aren't as good as this game. I have the original. I've made more progress learning to play guitar using that game than I ever did playing tabs. The key is to build muscle memory and learn your way around a fretboard, and Rocksmith masks that by letting you play a fun game where you play actual music and receive feedback along the way. If you're serious about learning guitar, this is a wise investment. It might not seem like it's worth it, but take it from someone who has the game, it's a great tool to have and it's actually quite fun once you get the hang of it.