12. A computer program product, comprising: a computer readable storage medium having computer readable program code embodied therewith, where the computer readable storage medium is not a transitory signal per se and where the computer readable program code when executed on a computer causes the computer to: create, responsive to determining to transition a voice call from voice communications over a voice network to streamed text over a packetized data network, a voice conversation correlation identifier that identifies the voice call and specifies incoming and outgoing streamed text data as part of the voice call; convert additional outgoing speech spoken by a user associated with the voice call to streamed text data; send the streamed text data identified by the voice conversation correlation identifier within an outgoing text stream over the packetized data network; receive streamed response text data identified by the voice conversation correlation identifier within an incoming text stream over the packetized data network; and convert the received streamed response text data within the incoming text stream to speech output as part of the voice call; where, in causing the computer to receive the streamed response text data identified by the voice conversation correlation identifier within the incoming text stream over the packetized data network, the computer readable program code when executed on the computer causes the computer to one of: receive text advertisement content within the received streamed response text data within the incoming text stream associated with a subject matter of the voice call and rendering the text advertisement content during the voice call; or receive text represented in a different language from a language spoken by the user and performing a language conversion of the text represented in the different language to the language spoken by the user, where the received streamed response text data converted to the speech output comprises the language-converted text.
12. A computer program product, comprising: a computer readable storage medium having computer readable program code embodied therewith, where the computer readable storage medium is not a transitory signal per se and where the computer readable program code when executed on a computer causes the computer to: create, responsive to determining to transition a voice call from voice communications over a voice network to streamed text over a packetized data network, a voice conversation correlation identifier that identifies the voice call and specifies incoming and outgoing streamed text data as part of the voice call; convert additional outgoing speech spoken by a user associated with the voice call to streamed text data; send the streamed text data identified by the voice conversation correlation identifier within an outgoing text stream over the packetized data network; receive streamed response text data identified by the voice conversation correlation identifier within an incoming text stream over the packetized data network; and convert the received streamed response text data within the incoming text stream to speech output as part of the voice call; where, in causing the computer to receive the streamed response text data identified by the voice conversation correlation identifier within the incoming text stream over the packetized data network, the computer readable program code when executed on the computer causes the computer to one of: receive text advertisement content within the received streamed response text data within the incoming text stream associated with a subject matter of the voice call and rendering the text advertisement content during the voice call; or receive text represented in a different language from a language spoken by the user and performing a language conversion of the text represented in the different language to the language spoken by the user, where the received streamed response text data converted to the speech output comprises the language-converted text. 13. The computer program product of claim 12 , where: in causing the computer to determine to transition the voice call from voice communications over the voice network to the streamed text over the packetized data network, the computer readable program code when executed on the computer causes the computer to detect a user request from the user to initiate language translation to the different language relative to the language spoken by the user during the voice call; in causing the computer to converting additional outgoing speech spoken by the user associated with the voice call to the streamed text data, the computer readable program code when executed on the computer further causes the computer to translate the streamed text data to the different language; and in causing the computer to send the streamed text data identified by the voice conversation correlation identifier within the outgoing text stream over the packetized data network, the computer readable program code when executed on the computer causes the computer to send the translated different language streamed text data identified by the voice conversation correlation identifier within the outgoing text stream over the packetized data network.