One possible caveat is Palmer getting hurt again. However they looked good against the Eagles and typically they don't play well on the East Coast. Their running backs had no trouble against what is normally a solid defense. They do need the kicker to actually make extra points though, but otherwise they looked pretty good.
The being just one win away for the first 12 win season in the team's history the Arizona Cardinals are among the hottest teams in the NFL right now. The Cardinals have depth are all the positions. Larry Fitzgerald is their leading receiver, but is backed up by John Brown, Michael Floyd and J.J. Nelson, all of whom can deliver the big catch. Then you have a defense that is fourth in the NFL in yards allowed per game and fifth against the rush.
The Arizona Cardinals are clearly one of the best teams in the NFL right now, but good teams come and go very quickly in the NFL. Super Bowl teams often miss the playoffs the next season. It is very difficult to know which teams will be good in any given season, because there is so much change, and a lot of randomness, in the NFL. Also, the most important position in football is quarterback, and Carson Palmer has been one of the best quarterbacks in the NFL this season, contributing greatly to the Cardinals' success. However, he is aging quickly and may not be as effective in the future as he continues to get older.
The Arizona Cardinals are a great team. They may even be the Super Bowl favorite from the NFC. I don't think we can call them an up and coming team in the NFL when they have an old QB and an older stud WR. I think to be considered an up and coming team, you need the key players to be younger.