Hi, Am from Hydbad. Am not sure how many felt the tremor. I haven't heard it from anyone here in hydbad till now. But around 315pm this afternoon i was reading newspaper in my office in sitting in the sofa set and i cud feel the sofa move a lil. Immediately i called my guys in office and asked them if they felt any. For which they said "NO". Then an hour later i saw the news on rediff saying that there was indeed a quake in koyna region. But please find out if there was any tremor felt in hydbad cos i felt the same.
It is difficult to predict earthquake at the moment, unless the behaviour of vibrations are studied in that area.However,traps were never stable, and is always prone to earthquakes.