SL resident Times Sands has published a 6 page article titled "A Technical Update on Second Life's Readiness for E-Learning", which is an informative look at where the technology stands today and what is still needed from an e-ducator's perspective.
It also contains a point to which I can attest to from first hand experience:
"... A reverse question is whether Second Life might be a useful venue for creating training content to be delivered in the real world? And the answer is a resounding Yes. Virtual films (called Machinima) are being made in Second Life faster and less expensively than would be possible in the real world (if they were even filmable in the real world at all)."... Mechatiki Production's eager staff are ready to take your orders.