Dunno, If you didn't put it there yourself then yes it's a big deal.
Try to store your bitcoin wallet and other bitcoin related actions on a safe PC.
Use another PC for your daily activities...
Well I downloaded it, and tried to run the rpcminer-cuda, but it didn't work..
I have my wallet on an offline PC, so it should be safe, unless the malware can jump on a usb stick and work on Linux..

Thanks for the info.
This possibly is a false positive identification, since you willingly downloaded the mining software. If you downloaed from a trustworthy source (original guiminer/poclbm threads/sites or the site of one of the big mining pools) you should be safe.
There are trojans with the prupose of sneaking mining software into systems and using that system's GPU and CPU power to mine for the author of the trojan, without the system owner knowing that his system is currently mining. Malwarebytes might have falsely identified the guiminer files as such a trojan.
I am not completely sure about that though. Maybe someone more knowledgeable can chime in.
Yeah, I've heard about those. My GPU & CPU are currently at around 0-5% so I don't think that's it, but who knows..
Because Eset didn't recognize it, it would seem like it's been "falsely identified", but who knows..
I'll probably keep an eye on my CPU/GPU for a while anyway.
Thanks!