I was very excited at the announcement of the 1D-X and I quickly put a preorder in, but I admit that I am now having second thoughts.
First, I am not a professional photographer by trade. I do take a lot of real estate photography - which pays for my equipment. For real estate I use a TS-E 24 II, TS-E 17, and occasionally a TS-E 90. From a pro standpoint therefore the AF doesn't do anything for me. The 7 shot bracketing is nice, but I can get by counting like I do today.
In terms of my hobby work, I primarily shoot nature and insects. My primary lenses for this are the MP-E 65, TS-E 90, 100/2.8 macro IS, TS-E 24 II, and 70-200/2.8 II. In almost all cases - even with the 70-200 - I shoot in MF. Therefore, for this scenario the AF doesn't matter much. The better viewfinder though will be very nice.
I currently shoot all of these with a 5D2. The biggest improvement the 1D-X will give me is high ISO. However with rumors of a high ISO 5D3 coming out sometime (probably EOY 2012) that would probably suit my needs as well as a 1D-X (if it truly uses the same sensor).
The one area where I do need AF is sports. In spring my two sons play baseball and for that I use a 7D + 300/4 and 70-200/2.8 II. As they play during the daytime the light is usually quite good and the 7D does a very good job. Otherwise I tend not to use my 7D as the high ISO sucks.
Finally I take a great number of photos travelling. For this scenario I take both the 5D2 and 7D and often have both cameras out at the same time. I typically put the 70-200/2.8 II on the 7D and the TS-E 24 II on the 5D2. If I go through with the 1D-X I would carry only that camera as I would sell the 7D + 5D2. For examples of places traveled to we did Uzbekistan+Tajikistan this year and have trips booked to Dubai and Tuscany next year.
The biggest argument for the 1D-X is I typically push ISO when travelling and taking hand held macro shots. The improved ISO would greatly help here, as would the better viewfinder. On the other hand, if I am patient enough to wait for a high ISO 5D3 then that should work just as well.
Generally I have always pushed buying glass over buying cameras, but I almost have the glass I want. The only lenses I really want are the 8-15 fisheye (which I will buy in March whether I pick up the 1D-X or not) and a good telephoto. The problem is for the $4000 I would save by not picking up the 1D-X now (rest of the money comes from sale of 5D2 + 7D) there really isn't a decent telephoto out there. The ideal lens would be the new 200-400/1.4x, 400/2.8 II, or 600/4 II but all of those are well beyond the budget. Of course I could always just keep saving until I do have enough.
I find myself therefore a bit conflicted. On the one hand a 1 series camera has always been a bit of a 'holy grail' to me and I have always wanted one. On the other hand I am not sure it is truly worth the expense.