I've also dabbled with a few open source LMSs and eventually settled on Moodle, simply because it's the one almost every school and university is using as well as lots of other businesses and organisations.
I see you're using Moodle too for your website, using a dedicated server as you said. What do you use for your interactive whiteboard and would you recommend it? i.e. Adobe Connect, Cisco Systems WebEx, Elluminate, etc.
I've just started looking into using AWS (Amazon Web Services) to host on. I've successfully used their S3 (Simple Storage Service), which is basically a bucket server, to host media such as video, audio and images. They also offer great support and tutorials which is handy for me because I'm pretty bad at PHP. My next step is to look into using their EC2 service (Elastic Compute Cloud) to host code and maybe even run a media server, like FMS, Red5 or Wowza to see how well that works out. AWS are fast, very reliable and so much cheaper than hosted or dedicated servers. Although, it may turn out that it'd be cheaper, in terms of development costs, to subscribe to a 3rd party media server for VoIP, message recording and the like.
I quite liked the idea that
http://livemocha.com/ have come up with, where students can record themselves speaking and submit it for peer review. Although I think having a standardised review system with qualified teachers would be the way to go for students enrolled on progressive courses.
I think the biggest challenge for on-line only learning is maintaining continuity for both students and teachers. The web does tend to be quite transient by nature and people tend to drift in and out of forums and other on-line communities. You may have experienced this yourself if you use any developer forums on a regular basis. Since e-learning is essentially an on-line community, I think the same applies.
Ideally, I think a blended learning with a balance of face-to-face classes, for the social and timetable aspects, and on-line resources, for studying, recycling and written practice is a good approach. For those students who are more comfortable with the ins and outs of on-line communities and web communication, VoIP, chat and web conferencing can also make studying more convenient and accessible.
Google Wave looks like it could have quite an impact on web conferencing, e-learning and the way most people communicate over the web. I wrote an article about it on my blog which includes the presentation video of Google Wave at the Google I|O conference:
http://matbury.com/wordpress/?p=263 Don't hold your breath though. It isn't even in Beta yet and there are a lot of problems with running it on hand-held devices such as iPhones.
