We're talking about 4e, not Iron Heroes. You might be able to drop an Arcanist into 4e and have it work just fine. He'd work just fine as a straight forward blaster. In fact he might be somewhat underwhelming if you do the math. (Sort of between a striker and a controller.)Iron Heroes was a disaster when it came to balance. Several classes were overshadowed totally by other classes. I wouldn't look for it for anything.
Looking at the math, an Arcanist isn't going to vaporize anything in 4e... just like a magic user in 4e. He's going to have a limited day, and when he goes a up a few levels, he's going to be able to do a few fireballs, and as everyone knows, fireballs aren't as exciting in 4e. But several might be fun.
Soo.. Magic user Class.. the basics like prestidigidation, light, etc, and *gasp* magic Missle (the new one), and toss Arcanist powers on top of that.