The short answer is yes. My wife and I did the grand tour with wine upgrades and had arguably the best meal of our lives. We thought it was better than Guy Savoy's in Paris. If you do the tour, be prepared for a four hour dinner. They have comfortable chairs by the way. We have not been to Avenues although a poster(Akatonbo) whose opnion I respect loves Avenues. One last thing about Alinea...Bono and Adam Clayton were there when we were.
Thanks for the compliment, hoppy2468! Yes, we love Avenues, and also loved Alinea. They are two different types of places, of course. I certainly agree that Alinea gave us the meal of our lives - it's hard to see how it could have been better. Since it's no secret how much it costs for the 24-course Tour with upgraded wine pairings, just let me say that if you plop down nearly $900 for a meal for two (tax and tip included), and walk away thinking it was worth every penny - well, that says it all, in my opinion.
Avenues is also superb - just a different style. There are also several differently priced degustations available - more choices than at Alinea. The food is more traditional (creative, but less cutting edge than at Alinea - which is not to sell it short at all).
Long story short - Avenues is wonderful - but Alinea is an incredible experience that no one who loves good food should miss.