I'd imagine, in all honesty, I'm not sure.
It would be interesting to see a more complete breakdown on complaints. I notice a big number in that article is that:
"65% said they bought their netbooks expecting better performance"
which leads me to think - these people thought they would perform similar to a dual core 1.6GHz machine. Yes, the atom is HT, but that really isn't the same as a dual core machine.
I'm thinking the number of satisfied responses might go up a bit with the newer systems with bigger hard drives, but I'd bet they would then start complaining about overall performance.
I know a lot of people that owned the Dell mini 9 that got all excited about the dell mini 10 once the 9 was EOL'd got really upset once they found out that the default config on the mini 10 had a 1024x576 screen rather then the netbook fairly industry standard 1024x600 - it may not seem like a lot, but when it's already hard to squeeze some programs to fit on a 600 pixel high screen (or depend on a specific min vertical rez), that missing 24 pixels can cause some heartache.
Plus, the performance of these things aren't stellar. They are good for what they are meant for (basic office work, net work, etc.) but people who want to watch HD videos or play games, etc. don't seem to always understand that a netbook isn't designed for that, and they are disappointed that they can't.
What is interesting is that some netbooks (ie: Asus N10) now have the 9400m graphics chipset, almost like they are trying to push an already taxed system to be able to do more.
I think netbooks will really shine once (if ever) intel comes out with a dual core atom. A low power, dual core atom paired with a 9400m with a decent 10" to max 11" screen really could replace a "full sized" laptop for a lot of people and keep them happy I think.
For a person who travels heavily for work and wants to really cut down on the size and weight of everything they carry, it's a great alternative. For someone who wants to be able to sit on the couch and surf the net and send emails, it's a great alternative. For the person who wants a general use laptop that can play some games - buy somethin else
Of course, regardless of why people are upset - the bottom line still ends up - they didn't really understand what they were getting. Either they didn't research it enough or marketing materials they looked at (without reading real reviews) didn't give them a clear enough picture to understand what they would be dealing with... Or they bought sight-unseen online without going to a store somewhere to really grasp what a netbook is.
Once again, just my humble $0.02 - but I would really be curious if there was a bigger more complete set of stats as to what people did and didn't like and what was enough of a dislike to make them dissatisfied overall.