Thank you all for responding - so the mystery still unfolds, eh? :)
For those wondering exactly where in Texas I am, I'm in North Central - in the Dallas/Ft. Worth area. Maybe that'll help in determining what birds they are, which I think takes the hooded oriole out of the running. If it helps at all, later on during the day I did spot another oriole in the same tree and the head was completely black - which I would think is a Baltimore. I agree that the pictures & colors of the birds are confusing because there's alot of shadow going on. I was hurrying in taking these pics and I was actually lucky to get what I got because after those 4 pics, they were gone. Wish they were better. :(
The thing that keeps stumping me on determining for sure what it is are the songs that I kept hearing, and recorded for the past week. When I found songs on the web for the baltimore, orchard & bullock's it seemed as though the orchard sounded more in line with what I was hearing.
Unfortunately I guess they've moved on because I didn't see or hear them today. And I even put out lots of goodies for them. *sighs*
Have I mentioned yet that this forum is awesome, as well as each of you? Thanks again for the help!