Linden Lab's Robin Linden has stated up-front that Linden Lab has no plans to raise basic tier or island costs this quarter. That doesn't mean it can't happen, of course, but it does strongly signal their intention to leave those prices unaltered before 1 January. Maybe things could jump if Linden Lab suddenly needed a cash influx before then, but it doesn't seem likely right now.
Linden Lab does indicate that the pricing of ... well, just about everything is 'under review' - but at this stage of things, that's pretty much a given. Almost everything seems to be under almost constant review.
