In reply to Sharp:
In terms of the old snow it's very much governed by aspect. I was on the Tarmachans on Thursday (23 April) - the last of the warm days - and we took axes in the car but left them there. We never felt need of them on the hill (we went east-west), as although there was a fair amount of snow on east-facing aspects it was all soft, easy-angled or - where steeper - avoidable. But anything much higher, or with a proper steepish exit slope, could have been problematic. There are also some awkward-looking corrie rims and cornices around.
West-facing slopes however were a different story, both where we were and on the higher things - it looked as though you could well have got up the western approaches to Beinn Ghlas and Ben Lawers without stepping in snow at all. For the Tarmachans the three of us were all in summer footwear - eg I was in Mudclaws and felt entirely happy.
Of course it also depends on what amount of snow gets put down this weekend - the forecasts seem to be saying smallish amounts rather than a major dump - and also how chilly it proves to be.