I've found the general Drupal group meeting a great place to learn about all things Drupal. From interesting modules, community initiatives, or presentations of sites/projects members have worked on. I've felt that the general group meetings have had to serve a very large audience (and it has done well in doing so) and I've greatly appreciated everyone's honest thoughts and opinions. By no means am I advocating that the general group meeting discontinue nor do am I implying I wouldn't continue to go to such meetings.
I have felt however, that for myself, it hasn't provided detailed (meaty) discussions on complex subjects that I as a Solutions Architect have to address on a daily basis. I'd like to get community feedback on an additional group meet-up event every month that may be 2-4 hours (or multiple days of the week) to discuss highly technical subjects. Maybe on a particularly difficult module or use case. Or even more formal "code" sprints on issues both core and contrib that the group would just like to "put to bed".
I'm talking about subjects such as customizing Drupal Commerce (products, shipping, taxes, coupons, shipping, cart/checkout, product field displays, etc), integrating Drupal with a single sign-on solution (and or LDAP authentication), evaluating community modules, configuring (and or building custom modules), and deploying a centralized media management solutions, to diving deep into using and or extending rules to meet a particular business case.
How about discussions more centered on analysis, strategy and or logistical subjects?
Subjects like requirements and use case analysis practices that drive features specifications and business object modeling. Network/server analysis where you would audit the existing infrastructure and business systems to then provide a strategy to either migrate to Drupal or devise a strategy to sync or migrate data/media from existing business systems (via SOAP/Rest APIs using rules triggers or custom modules) into Drupal. How about discussions on data analysis and conversion/migration strategies from one business system (or CMS) into Drupal?
But this is just a few examples of the more detailed, deep discussions I'd like to have discussions on. Perhaps we help someone with a particularly difficult problem, or we prepare each other to when that big issue hits on the next project. Or better yet, star to learn about eachother's strengths and know who to call if you need help on a subject for a client (for paid consulting of course).
I don't want to exclude anyone from the conversation but, I'd assume people who'd like to contribute to such conversations would have several years of experience with the modules and or Drupal core. In some cases you may also have experience developing in other languages, frameworks, and or platforms. Such as Java/J2EE, C#/.NET, Python, Ruby, etc.
I've talked with my employer (Isite Design inc) and we've just moved (well 3-4 months ago) into our new building and if we can schedule it appropriately we could use our brand new, dedicated meeting room for the meetings (which just so happens to be one block away from the luckylab).
So what do you think? Please chime in on interest, subjects, etc.. as I would be happen to host/organize this event.

Comments
Centralized Media Management
I would really like to think out loud about some of the architecture issues you mention. Particularly centralized media. At PSU, we have a HUGE amount of duplicated files (branding resources for site owners to use) in our multisite. We were thinking there ought to be a way to have one storage tank that can hook into Media management transparently.
I would relish the opportunity to talk about these complex problems and how to solve them.
it's not perfect but this is
it's not perfect but this is the solution we're using. Basically a drupal site that is an asset management backend, hooked into via buttons in CKEditor. Uses short codes similar to wiki markup / (i think) media module in d7 (this is d6).
http://elearning.psu.edu/elearning/elimedia-asset-management-system-tuto...
Ex Uno Plures
http://elmsln.org/
http://btopro.com/
http://drupal.psu.edu/
Interesting
Novel idea, i will have to dig in and see if something similar can work for D7.
time
I like the idea. If you have these meetings, I will try to attend (finding the time is always an issue).