Site Recycle Bin
Most of us know that currently if we accidently delete a site or site collection, we are in trouble. We need to restore it from the backup. Service Pack 1 will introduce Site Recycle Bin functionality that enables recovery of site collections and sites. With Service Pack 1, administrators can quickly and easily recover site collections and sites accidentally deleted by their owners in a process similar to that of the Recycle Bin we have for Lists, Libraries, and Documents.
Consistency enhancements
Most of the administrators know the pain of making profile synchronization working properly in SharePoint 2010. This upgrade is definitely useful for profile sync.
Shallow Copy
Service Pack 1 reduced the overhead of moving a content database where a remote BLOB was enabled, by "shallow copy". New Shallow Copy functionality with the Move-SPSite CmdLet enables moving site collections between content databases without moving the underlying unstructured data, i.e. Microsoft Word documents, PowerPoint Presentations, etc. significantly increasing performance and reliability for organizations using Remote BLOB Storage by simply updating the pointers to those objects in the destination content database. If anybody wants to know more about Remote BLOB configuration in SharePoint 2010 please read my earlier article.
Increased browser support
There should be some enhancement in the browser support. You can get the more details from the below browser support article
http://technet.microsoft.com/en-us/library/cc263526.aspx
Increased Power shell support
New Powershell cmdlet for moving Site Collections between databases without moving content back in the database when using RBS. And there are some Improved backup / restore functionality for SharePoint Server.
But my recommendation is to first test Service pack 1 in your environment and if everything is working properly then go ahead and deploy it. Profile synchronization and some advancement in claims will be momentously mentioned features.