Cysive, a consulting company - turned product company has released a whitepaper documenting that, in-deed, native calls are faster than soap calls. Congratulations on this discovery! It only took 34 pages for them to unearth and articulate this finding.
I think my favorite line in the press release is:
"Performance of Conventional Web Services Stack Too Slow for Large Scale Systems & Data"
After reading the report, I figured it would be better to not comment on it and just let the readers come to their own judgement.
The unfortunate news is that Cysive is only losing about $8 million a quarter and they have about $75 million in the bank. Thus, we have the wonderful opportunity of getting this kind of "insight" for at least another 7 quarters. Thank God for big IPO's.