This 0.3 rating thing for all news on FM may not just be limited to Merlin's Chicago station, nobody knows more about all news radio than CBS, and their new WNEW-FM in DC also managed a 0.3 in the latest rating period. However, it's also its first rating period out of the gate as an all newer.
It should be noted that since CBS switched the format last December the WNEW cume has been sliding. In the Holiday ratings it managed a cume of 353,000 by playing Christmas music, it then played the "History of Rock and Roll" and cume slipped to 179,000 and now with all news it's down to 131,000.
It might also be noted that both Merlin's all news in Chicago and the new CBS all newser in DC are both up against long-established all news operations that are also heard on FM, so unlike Merlin in New York, and soon in Philly, they have strong competition on the same band.
In New York it does seem that Merlin is slowly finding a larger audience, WEMP's cume has risen from 540,000 during the holiday period to 637,000 most recently. If it can continue that growth rate, it could have a larger cume than WOR before the end of summer, a larger audience than WABC by the end of the year, and it could catch up to WCBS-AM by sometime next Spring. But it wants to play in the same demos and with the same kind of audience numbers as other NYC FMs, and that's a whole different ball game and a much bigger mountain to climb.