If click on the link in the OP, you would see that a ATI 5770 was used in the test and it lacks double precision.

This is great news. Hopefully we get good support for our gpus and single precision gpus would be supported. I have 5 gpus and if gpu app would be stable and make good use of my gpus i would dedicate all of them to this project.

Any ideas if SLI/Crossfire configurations will be supported?

I'm curious, what grid project support this now?

Dual cards such as HD 5970 have Crossfire enabled internally and it cannot be turned off. This sometimes causes problems with OpenCL applications using 2 full CPU cores due to each GPU core using a full CPU core. It's kind of a "busy wait" thing.

The PrimeGrid ATI PPSieve OpenCL application suffers from this problem.

You can assign both GPU cores to a single CPU core with programs such as Process Lasso but it's a messy workaround. Or you can use an app_info.xml file with avg_ncpus value of 1 to leave 2 CPU cores free to support OpenCL GPU processing if you have 8 CPU "cores". Those with only 4 core computers with no hyperthreading and those with 2 dual GPUs do not have the same flexibility though.

If you don't do anything and the default avg_ncpus value is too low it causes your CPU to become overcommitted if you are also processing BOINC CPU tasks.

This is why you need Crossfire support, to be able to run an OpenCL task on each core of dual GPUs without eating up your CPU resources.