Interesting, but I'm not sure it's right. I'd say iSync is more like Microsoft's ActiveSync rather than Plus Sync & Go. ActiveSync synchronises contact, calendar, and task information between a PC and a PocketPC, while Plus Sync & Go sounds more like an AvantGo competitor, in that it synchronises online content.
In other words, I'm not sure why Apple would be in a hurry to release a synchronisation tool that doesn't compete with Microsoft's latest offering.
 I suppose I should mention I work for the company that owns AvantGo.