Perhaps I can help by being a bit more specific:
Bitcoin
Ethereum
Monero
Factom
Synereo
Dash
Storj
Given that list, can anyone say whether Windows or Linux would likely be the first release platform for their wallets/nodes/stuff...?
You're listing the bigger, more established coins here... I don't think there will be a (big) difference between the release times for windows or linux wallets for these coins.
I was talking about new coins with a small community.
I'd personally go for linux, but i think it's just a matter of personal taste...