As if things weren’t bad enough already for print publishers, the United States Postal Service is raising rates in May by around 4%.

The rate hike, which will apply to first class, standard and periodical mailings, is one more stake in the heart of the already troubled print media industry. In times such as these, it’s hard to imagine an ad rate hike that could realistically cover higher distribution costs.

While small, this rate hike is added incentive for publishers to reconsider their digital strategies. The venerable Christian Science Monitor has already announced plans to cut back its daily print publication to a weekly edition, while continuing to update its web site every day. With the cost of moving dead trees from here to there, expect other print publications to follow suit.

The upside, of course, is digital. Like it or not, a rate hike will force publishers and cataloguers to concoct more robust digital strategies or risk extincition. When online components are must-haves, rather than nice-to-haves, it pushes the channel forward. Stay tuned for broader adoption of email, RSS, online loyalty programs and of course, more online content.