CAUTION:  Microsoft released SP3 for Exchange 2010 and it has the same 'bug' that SP2 had.  If you
attempt to install the SP with an execution policy defined, the installation will fail and your server will be inoperable.  The only recourse is a /m:recoverserver.  Why they allow the install to run instead of just checking for this condition is crazy!

http://support.microsoft.com/kb/2810617/en-us?sd=rss&spid=13965

Another iOS-Activesync bug has been found that causes excessive log generation caused
by iOS 6.1 devices.  Apple really needs to get their act together on this as it's been a recurring
problem.

http://www.sharepointpromag.com/blog/tony-redmonds-exchange-unwashed-50/exchange-server/apple-ios-61-upgrade-excessive-transaction-log-growth-145223

Seems like the consensus from many people is Exchange 2013 is not ready for primetime:

http://www.exchangeranger.com/2013/01/exchange-server-2013-missing-and.html

Exchange 2013 reaches RTM:

http://blogs.technet.com/b/exchange/archive/2012/10/11/the-new-exchange-reaches-rtm.aspx

Exchange 2010 SP3 is coming early next year!

Looks like MS will release Exchange 2010 SP3 in the new year:

http://blogs.technet.com/b/exchange/archive/2012/09/25/announcing-exchange-2010-service-pack-3.aspx

Support for Exchange 2013 coexistence (schema update required) seems to be the big new feature.

Exchange 2013 Preview is out:

Now only 2 roles (back to 2000/2003 days)
No RPC client access - Outlook connects via RPC over HTTPS (wow)
More progress in trying to kill public folders
No co-existence with Exchange 2003

Lots of other things as well.  Interesting direction MS is going now, we'll see if
it's the right one in a few years.

http://technet.microsoft.com/en-us/library/jj150540(v=exchg.150)

Exchange 2010 Junk Email filter is broke... duh.

This has been broke for a while but just recently was documented by Microsoft:

http://support.microsoft.com/kb/2655142/en-us?sd=rss&spid=13965

Even though there is no resolution listed in the article I've been told by a trusted resource
that this fix is in Exchange 2010 sp2/ru3.

YMMV, be sure to test!