Hypericum has been shown in multiple trials, and in a large meta-analysis to be not inferior to some other SSRI's (direct comparisons vs. paroxetine and sertraline) and is about as effective vs. low-dose MAOIs. As we know, MAOIs and hypericum are not to be co-administered.
Some of these major randomized, double-blind, studies have come from Germany. Therefore, one could assert that the push for the use of hypericum in Germany isn't surprising.
I think it hasn't gained as widespread acceptance in the U.S. secondary to it's non-FDA approval for clinical depression, and multiple drug-drug interactions. Short-term studies have showed good tolerability, but of course, much larger, longer term studies should be carried out before it is deemed safe or acceptable.