I was fascinated by Jeff Muir's account of how the ICA web client came to be written, and also by the timing of when this happened (much earlier than I realized). It brought home to me again the curious arc Web Interface is riding, from the early days of the Web when it was a novelty to be able to run applications from a web browser, to the point we are at now where it is getting increasingly difficult to run ICA applications from a web browser, at least with the technology we have today. Making sure we are in a better place a few years from now concerns me, and makes me wonder if we need a step-change in technology.
We've known for some time that it is getting harder, and that people are running into more and more situations where Web Interface isn't working properly and they can't get access to their applications. It isn't just executives using the kiosks in airports and hotels - though you can imagine how much visibility that gets when a company has just put in a shiny new Citrix system for remote access! It also matters for customers wanting employees to be able to access critical applications from home, or from anywhere they might be stranded in a wide-scale emergency.
The problem is that security concerns have come to the fore, and browsers are increasingly trading off usability and convenience (or rather the apparent convenience you enjoy before your PC stops working for you and opts for a life making money for spammers) for better security. Browsers themselves are including more security mechanisms like the IE Information Bar introduced by Windows XP SP2, pop-up blockers and the like have become de rigueur it seems in almost any product with an Internet focus, and security suites are hooking into almost everything that's happening on your PC to block bad behaviour.
This decline in usability unfortunately goes to the heart of the Citrix value message, that access is provided from any device over any connection anywhere. Web Interface is the primary means we have of delivering on that promise, with the Internet and web browsers taken for granted as the ubiquitous baseline we can assume to exist (almost) everywhere.
So it's a big deal for us that WI is hitting more and more problems that undermine this essential role, and I am pleased to say we are now doing something about it. We can still use your input and guidance though, to help ensure we are focused on the right aspects and make the right tradeoffs.
The approach we are taking is one that has been pioneered already; you can see a good example in action here. In essence, the approach is this: accept that we cannot always accomplish what the user wants, or not always as easily or as well as the user would like. Instead of pretending that we can always launch applications at the click of a button, and treating the small matter of ensuring the user's computer has the necessary client components and security settings as a kind of after-thought, lets make that process an essential part of the user experience.
And if we can't launch applications (for reasons beyond our control), lets be sure tell the user so clearly and promptly, so they don't waste any more time trying. If we can say why, they also may have the chance to get something done about it; maybe convince kiosk owners to pre-install ICA clients for example.
I'm sure this is a topic that will get discussed a lot more, here and elsewhere, so for now I'll just whet your appetite with a screenshot from a prototype we've built recently which gives you a flavour of how we are intending to start following this approach in the near future. 
As I said in my initial post, this forum is an opportunity for you to give feedback directly to the Web Interface team, and there is a good chance that we will be able to act on your feedback and incorporate good ideas, if not in the next release then as soon as we can. So, let us know what matters to you, and where you would like us to concentrate.
Cheers,
AndrewI
Posted by 
I guess you probably know that IE already has some interesting policies relating to admin-approved ActiveX controls? As far as I'm aware, it isn't something we've had much feedback from customers about, but I'm pretty sure there are some that use them. Cheers, AndrewI
Great discussion Andrew! A few comments... First, I think it's clear that WI is the future of Presentation Server / Tarpon access, be it via a browser or via PNA, and I do agree that browsers will continue to get more locked down, so this is a crucial discussion. I know this isn't really a WI issue, but I was flabberghasted when I learned that the motivus / live edit / dimmer switch / limited access functionality of AAC requires a client side ActiveX control! To me, part of the beauty of the live edit concept is that if you don't have real access, then we can still deliver basic app functionality. (I know, I know... it's really about security, not access in this case, but I digress.) Anyway, at BriForum last week, Simon Frost mentioned that ICA client 10 will not require admin rights to install. Will that help in these cases, or do you see this more as a launching issue? What are other companies (Abobe w/ Flash, etc.) doing in this space? Is there anything to learn there? Brian