Windows Phone Thoughts: Is Windows Mobile 2003 Slowing Down the Dell Axim X5?

There's an discussion going on here about the Windows Mobile 2003 upgrade running very sluggishly on upgraded Axims, but how it's fast on new Axims that ship with it. Very interesting - I'm still waiting for word of availability of the upgrade in Canada, then I can do some Spb Benchmark testing to see if it's slower. I wasn't even aware that Dell was shipping the upgrade yet (I thought it was due later this month), but apparently some users have received it. If you have comments on this issue, please post them in the discussion thread linked above.