> I believe this will give us something closer to oracle where if one
> transaction is updating other transactions can still read the old
> data. Is this correct?

Yes, this [is correct](https://stackoverflow.com/questions/27499/database-what-is-multiversion-concurrency-control-mvcc-and-who-supports-it).

Well worth reading the links in gbn's answer and I believe the same applies to Oracle's default MVCC as to SQL Server in Snapshot Isolation mode. I would add that if you understand the potential pitfalls, IMO the benefits far outweigh the added difficulties (speaking from an Oracle perspective) - and of course some locking problems legitimately go away, that is the point of MVCC (there is also a class of locking problems that will not go away due to code issues, but I am assuming you understand this).