Just another opinion here, but here's what I think. In a word, "Maybe".
how's that for riding the fence? First I'd take a look at the amount of wood you might plan on running over the jointer. If in your opinion, it would be a fair amount..........well then..perhaps a good investment to be sure. However, would accomplishing the same ends via different means override the investment? If you're planning on using smallish to medium sized boards, ski's and a table saw jig would accomplish pretty much the same end result...
I'd say that if you already own a planer then yes it would be a good investment. With the jointer you're essentially working on 2 sides of the board. Truing up 1 edge and one face. Once this has been accomplished, its off the the planer or sander to do the opposing face and then to the table saw to run a parallel edge. Aside from the occasional novelty board I'll pick up on Ebay or here and there, 99% of the wood I get is roughsawn and requires my truing it up. Nice thing is, I can true it up to "MY" specs!!
I've a 6" Craftsman Professional jointer and I have to say, I really would NOT want to do without it. The only thing I would change would be I wish it were an 8" jointer. She gets used on just about every piece of wood I bring into the shop. From shorties to 8 footers. The cut it leaves behind is acceptable. I say acceptable due to the fact that the knives are about shot and should be replaced soon. When new, and set up properly she leaves behind an excellent finish (for a jointer!!) Noise is not a big issue. Need to be a bit careful when working with figured woods, tearout can be a problem and almost impossible to avoid unless you have one of the high end spiral cutters. An expense comparable to the cost of the jointer itself in some cases. On occasion the chips do clog up the unit, usually when I'm rushing things *L*. A dust collector is not a must, but unless you want to spend a good deal of your time with a broom and dust pan in hand, its handy to have. Setup is pretty straight forward and should be checked regularly. Keeping the knives sharp and a little rust prevention is about the only maintenance.
BTW... even if you don't have a planer, a well tuned #4 or #5 handplane along with a pair of winding sticks and a good straightedge can make quick work of truing up that 2nd face with a little practice.
SO, I'd say if ya got the funds, the room and the wood, most likely an investment you will not regret....
edit to add: I've found that when chipout is a problem, slowing down and shallowing out the pass has helped considerably.....grain direction over the knives is a biggie!!!!