The folks at CNN Money report that Palm’s share of the smartphone market has risen due to excellent sales of the Centro:

Palm Inc., a pioneer in the category along with RIM, also picked up market share in the first quarter, when it grabbed 13.4% of smartphone sales, up from 7.9% in the fourth quarter, IDC said.

“Palm also did really well. It posted a sequential gain mainly on the strength of the Centro phone,” Llamas said. The Centro, a smaller phone than Palm’s Treo models, came out last fall for the Sprint Nextel Corp. network and was launched by AT&T Inc. in February.

But Palm’s market share is down from 23% in the first quarter a year ago, apparently falling victim to the iPhone, which went on sale late last June

Apparently, the Centro really does sell exceptionally well - I am pretty sure that Palm can survive for at least another year due to the Centro revenue. However, Palm getting fat does not guarantee rich developers and a thriving user community: developers like Resco have reported seeing little to no Centro sales in a recent TamsPalm interview.