This icon often appears on my phone, when I am in my home area. I shouldn't be roaming at home in the middle of the city, but the icon often appears around town too. This isn't my first phone with Sprint, so I know I have good coverage here and my 8130 gets a much stronger signal than my A900 did. Just an observation.
I think it is roaming... I had it for a bit today, and my data was cut off while the triangle was there which is what roaming causes. It's gone now that I'm back in town though.
I had an A900 as well, and in my experience... the Pearl has weaker reception. When I had the triangle today, I was at a friends house, which no matter what phone I've used, signal's terrible there.. My A900 would have a weak signal but wouldn't roam. The Pearl drops in and out of roaming in his house, depending on where I happen to be, sometimes data works fine - no triangle, next time I pull it out of my pocket, data's off and the triangle is back.
I have the triangle indicating roaming on my 8830. However, many cell phones show a triangle when the encryption for your voice calls has been turned off...usually meaning that your conversations are being listened to. This has happened to me too (I'm in Russia - security services have at times received access to any and all phone conversations in Moscow, and you see that triangle appear)....
