XYZcomputing have a look at the Dell deal and comments on whether it is as positive as the reactions have been so far.
Read it here
There are many upsides that come along with the Dell/Ubuntu deal. These have been widely discussed, such as hardware compatibility, user support (a mixed blessing if you have to work with Dell), the ease of purchasing a custom Linux machine, and the competitive prices that Dell can offer. During an initial consideration is seems like there are no serious downsides to this, after all up to this point there have not been many places to buy a custom computer with desktop Linux pre-installed. Even so, we have very few details on how Dell with actually go about offering Ubuntu so there might be some surprises on the way. What could go wrong with Dell offering Ubuntu? While we have high hopes for it, there are always concerns.