Beth,
This is a very interesting question, and I think important also.
As an IT infrastructure manager I had staff supporting large Citrix farm environments and as a small business owner I've used Terminal Services on Windows Server 2003 to host Quickbooks.
Terminal Services for Quickbooks worked well except the Quickbooks licensing system does not explicity support Terminal Services access for multiple users. I was able to get it to work, but eventually gave up when trying to upgrade Quickbooks and needing to re-activate licenses, etc.
Even though Quickbooks does support a Client/Server type architecture, their documentation and support people assume the Clients will always be on a PC, instead of being Virtual Clients. So, I was never able to find good documentation and I'm not sure the licensing system didn't cripple this architecture in some versions of Quickbooks.
The good news, I think, is that in all our work hosting literally dozens of applications on Citrix Farms, there was always a way to "trick" the application software into thinking it was running on client PC's, separate Client/Server machines, etc. The Citrix administrator is typically well versed in setting up config files for the Client Session environment to fake out the application software. I think in general more difficult applications ran better when Citrix was virtualizing the entire Desktop for the user instead of just the application. When Citrix virtualizes the entire desktop more environment variables and attributes related to printing, drive mappings, etc. get virtualized automatically. This might be obsolete thinking though.
From what I can determine, Method has a fairly simple architecture consisting of 1) the Browser based application and 2) the Synch Engine. Hosting the Browser Session successfully on Citrix should just require making sure the Java or ActiveX plugins etc. are available to the Broswer and tweaking the security settings of the Citrix Server hosted browser to allow Method to do it's thing. As long as you don't have an overly restrictive corporate security policy, the server admin should be able able to keep the browser config flexible enough for Method and it's needs for client side browser plug ins, etc.
I think the key to a successful installation of Method in a Citrix Environment is the configuration of the Method Synch Engine. I think that typically Method assumes you will have a Synch Engine client installed on each client PC such that there is a one for one relationship between Synch Engines and Browser Sessions. I am not sure, but I think this is recommended since you want to see any changes to the Method data tables immediately updated to the Quickbooks file in case a user is switching back and forth or if there are data table race conditions. For example there may be cases where Quickbooks must complete the financial posting of data to create a new journal entry that will then upload to the Method tables for further processing.
I am not sure how Quickbooks handles user access licensing for the Synch Engine. When you allow the Synch Engine access to the QB file, does QB see each listener as one user, or is it granted as an application without counting number of users. It appears like it is granted as an application, but I'm not sure.
So, you might need to have the Synch Engine installed for each Citrix Session just as each Citrix Session would need the same Browser configuration. This might need to be done from within each named Method Users Citrix Session for Method to install and configure the Synch Engine to that particular users Method User account. Or, it might be that the Synch Engine is not Method User Login dependent and the Citrix Administrator can install it for all users and the Synch Engine only comes alive when activated by the Browser session or from within the users Citrix Session.
Although I have not been able to confirm this with Method, and it might be dis-recommended, I thought there might be an opportunity to setup a single Method Synch Engine on a Server to cut down on network traffic to the server and Internet connection bandwidth. I don't know, but I am assuming that multiple users could potentially generate redundant synching operations. I'm not sure how all that works though and I think Method is continually innovating the Synch algorythm's to minimize any potential performance issues.
Anyway, I am a huge Citrix/Terminal Services fan and Citrix has a huge support base for hosting any application. It's been a while since I had experience with it, but even back in the day we always found a way to host the application. The TS protocol is very efficent and makes it much easier to provide support for staff working from home over various bandwidth connections.
Keep us informed.
Cheers,
James