Here's a quick comparison between the Toyota Hilux and the Holden Colorado formerly known as the Rodeo or otherwise known as the Isuzu D-MAX. Since it made by a number of countries you can expect that there will be an endless number of variants and names. Both are 2010 model year variants.

The Colorado we looked at was the LT-R version but there cheaper variants. The dual cab or crew cab 4x4 version only comes as a diesel for 2010 but for 2011 we saw a few that had the 3.6 litre V6 as an option.

The Holden Colorado is a decent enough utility but honestly over priced in the category. We wouldn't pay that much and have to look at it and drive it everyday and actually think its worth the money. It is really targeted at commercial users rather than private buyers.

Holden Colorado
VS
Toyota Hilux

The diesel or petrol engine are not the most advanced available but clearly in the same field in terms of technology and power.  We think the V6 is related to the one used in the Holden Commodore. Regardless the dated manual transmission and automatic will be noticed.

The Colorado is smaller than the others in terms of measurements and when you get into the car it is clearly a utility truck rather than emulating a regular passenger car. Sorry guys but it looks and feels too commercial like. I guess that would appeal to the commercial guys but not private buyers. The Colorado does not have a big price advantage either.

We couldn't live with this as a replacement for the Prado or even the Hilux and certainly not at these prices. Even if the cheaper version was taken into the comparison would not change the outcome. It's just not well equipped or have quality materials for a modern family vehicle in 2010.

As for its competitors stay tuned for some more comparisons over the next few months.  Our leader board reads like this (At the time of writing in early 2010 - Revised for 2011):
1 - Navara
2 - Hilux
3 - Triton
4 - Colorado
(Feel free to disagree.)

Note that you should always check with your local dealer for correct and up to date specifications and pricing. 
 

Toyota Hilux
2010 FROM $44,500-$56,000 AUD

Holden Colarado
2011 FROM $38,200 - 50,690 AUD