Someone was grumbling in my hearing (on a channel on a private IRC server, actually) about some of the problems Web systems like `e-commerce'[1] have.
After a little ranting, I came up with a summary which I think encapsulates my attitude towards it fairly well:
"Doing state over the web is taking a stateless protocol (IP), layering state atop it (TCP), throwing that away again (HTTP), and then trying to resurrect the state under the artificial restriction that one of the endpoints (the Web server) isn't able to initiate traffic to the other (the Web client). If you want TCP, you know where to find it."
[1] What an arrantly silly neologism. Telephone orders aren't called `t-commerce' (or `p-commerce'); this term is all about buzzwords rather than content.