Shares of Comcast fell as much as 8% in morning trading, before closing down just over 6% at $41.70, after the Philadelphia-based media giant reported a slowdown in new subscribers, as it spends more to lure them. A gain of just over a quarter of a million new subscribers is “down sharply from last year” — and one-third of those “new” subscribers had previously been receiving the service under a temporary free program but weren’t reported by Comcast until this morning’s quarterly earnings disclosure, analyst Craig Moffett told clients in a report this morning.. The stock fell below $41 for the…