The thing that no one is mentioning that will have the biggest impact on sales is this :
The HP name.
It's HUGE. They have a reputation in the industry, the name carries weight. The average Jane doesn't buy an iPhone because of the retina display or the 1ghz processor, she buys it because it's an iPhone.. it's Apple.. there's a brand recognition there. Hell I know quite a few non-computer savvy people who own various Android phones and refer to them as Droids. They don't even understand that the Android OS is used on phones that are not "droids".. they don't know CPU clock speeds, internal RAM amounts.. they have no clue what Froyo and Gingerbread are. They bought the phones because they were SOLD those phones.. their friends had them, they saw them, they liked them. End of story.
Marketing will make or break the HP Pre3, Veer and TouchPad. Plain and simple. Cool commercials highlighting the right stuff + well trained salespeople + nice looking, funtional products = sales. I have confidence that HP will be able to do what Palm did not have the financial resources to do : market the HELL out of webOS.
I, for one, will be there on Pre3 launch day with wallet-in-hand. If I have to switch carriers, so be it. I believe in webOS and I will support HP/Palm once again.