I highly recommend all these shows, and with the strike talks still going nowhere, maybe you will have some extra time to check them out. I tried to stay with shows similar in concept and themes to Heroes but feel free to add your own recommendations.
Carnivale - A great series from HBO that deals with extraordinary people and battles of good/ evil. This series is very comic-book like as is Heroes.
The Lost Room - A miniseries from the Sci-Fi network. This series is similar to Heroes except instead of people havingspecial powers, certain objects havespecial powers. Overall very addicting and fast paced.
Battlestar Galactica - Absolutely great series from the Sci-Fi network. Set over 5000 years in the future, this space drama deals with many themes including good vs evil, what it is to be human, and the survival of the human race. Very very good sci-fi series.
Lost - This is a no brainer, you must have been living in a cave for the past 4 years if you havent heard about this show.
Jericho - I'm halfway through the first season, but its pretty good so far. Kind of like a mix between Battlestar Galactica and Lost.
The Wire - Absolutely the greatest show I've ever seen, and possibly all time. This show is not in any way similar to Heroes but I couldnt resist putting it on the list. Words cannot describe how truly great this show is. Well they could, but I would be writing for the next 8 hours and I dont feel like doing that. Theres a reason EVERY critic loves this show. In fact the 4th season has a 98/100 rating on metacritic.com - the highest ever for a tv show. Please check it out.