concurrency control explained
So, I just came from seminar led by Kalen Delaney, guru of SQL Server (any version), organized by Ireland SQL Technology User Group. The whole event was sponsored and hosted by Microsoft. I must say, I am impressed. Kalen was able to sort out and put into proper drawers all bits of knowledge I had before and stuff a whole lotta more into my head. She talked about concurrency, transaction isolation levels, differences between optimistic and pessimistic locking, blocking and diagnostic tools, and at the end about gotchas related to (nolock) hint, overused so eagerly by many devs (I confess, I used this hint myself ;))
You can find tons of good info about execution plans and isolation levels at Craig Friedman's blog here.
Overall, it was a very interesting day!