Solar hot water, tax credits

There was an opinion piece, written by a physics professor, in the New York Times last week. It's not earth-shattering, just points out that while solar hot water is less well known than photovoltaic, electricity-generating panels, is more efficient and less expensive.
They are easy to install and do not have the dramatic reduction in production caused by partial shade that plagues the photovoltaic panels.

He also mentions tax credits, and this part is confusing. The Times posted a correction, which does not help that much. I went to energystar.gov and found this:
Solar Water Heating
* At least half of the energy generated by the “qualifying property” must come from the sun. Homeowners may only claim spending on the solar water heating system property, not the entire water heating system of the household.
* The credit is not available for expenses for swimming pools or hot tubs.
* The water must be used in the dwelling.
* The system must be certified by the Solar Rating and Certification Corporation (SRCC).
Credit is: 30% of cost, up to $2,000
There is a link to IRS form 5695 for this.

For photovoltaic panels, there is a straight 30% credit, with no cap.
Sweet.

The caps were raised and deadlines extended with the 2008 stimulus package. And these postings don't seem to reflect the 2009 stimulus package just passed. The numbers I have seen on that suggest a 30% credit is still in place, but perhaps the $2,000 cap has been removed for hot water. I'll keep my eyes peeled to see if I can confirm this.