I've built a production entity resolution system using 100% Go. It implements a map/reduce model with many workers and multiple (for failover) masters. All data is held in memory for speed purposes. Things that are amazing about go: fun and fast to develop in; beautifully designed (rockstart founding team, than you!); RPC, net channels, and maps and strings, to name a few. The ability to quickly create servers to host business logic. Interfaces and "inheritance" model are both very elegant and clean. Compile times rock. Everything was built with the standard Go (pre 1) install; not a single other package was needed--the very complete standard lib is a blessing.
Two "could be better" points. Go has a hard memory limit per instance of ~ 15 GB; bad when you want to pin lots of data in memory. Russ says this issue is being tracked (2142) and will get fixed after Go 1 gets out the door. So patience will fix this one.
Second, there needs to be more examples of Go code out int the wild for others to share and look at. Using the template package got me stuck, for example, and seeing code cleared up my issue but that was hard to find. This we can all help with by using Go and talking about it. Again patience takes care of this issue as well.
Other than these items, do yourself a favor and start using the magic that is Go!