I don't think the concern is that they lost... I think the concern is that they blew a huge lead, on their home floor, where they have been essentially undefeated all season.
They needed bench production. What the Cavs did with LeBron not on the floor was ultimately gave the Cavaliers a loss. Yeah they blew a huge lead, how did they blow it? Role players not scoring. It really came down to the final buckets of that game. Lewis hits a giant three when Varejao fails to come back out on perimeter defense. The Cavs get a no call on a LeBron charge to the hoop, a missed attempt, and inches away from sealing it with an impossible shot.
Yes, the Cavs lost. They didn't look bad all around. To not get any form of bench production (5 points from Joe Smith) and still only lose by one. No reason to hit the panic button just yet. The starting five played decent, they needed more from Mo and West, better percentage shot anyways.
Varejeo, Z, and Big Ben. These guys need to keep a body on Dwight the whole time. I know that Z/Ben can't match Dwight for speed, and Varejao isn't big enough to handle Dwight. If you keep a body on him though and don't allow him to get those easy baskets then your looking a lot better game 2 and on then you did game one.
The Magic are a team that lives by the 3pt line. Early on the Cavaliers perimeter defense was outstanding, holding the Magic under 35% shooting. In the second half that jumped up to 50% (?) and the Magic got 8-0, 6-0, 7-0. Spurts that got them into the game. If the Cavaliers could of disrupted those spurts it's an entirely different game all together.
It's going to be interesting to see how the Cavaliers answer back in game 2. Cavs also need to win on the road. One thing they've got going for them is LeBron plays better away from the Q this season. If they can get better bench production, show their depth and stay physical with Orlando this series could take a drastic swing. Right now it's looking like a seven game series.