Communications system including aggregation server for determining updated metadata of e-mail messages and related methods

1. A communications system comprising:

an e-mail server configured to store pushed e-mail data and metadata associated therewith; and

an aggregation server configured to

download a first set of metadata of the pushed e-mail data,

generate a first set of hash values corresponding to the first set of metadata;

download a second set of metadata of the pushed e-mail data,

generate and store a second set of hash values corresponding to the second set of metadata, and

determine an updated set of metadata based upon a comparison of the first and second sets of hash values.

2. The communications system of claim 1 , wherein the aggregation server is also configured to push the updated set of metadata to at least one mobile wireless communications device.

3. The communications system of claim 1 , wherein the e-mail server is also configured to store unpushed e-mail data; and wherein the aggregation server is also configured to download the unpushed e-mail data, and push the unpushed e-mail data to at least one mobile wireless communications device.

4. The communications system of claim 1 , wherein the first and second sets of metadata respectively comprise first and second sets of e-mail server defined metadata.

5. The communications system of claim 4 , wherein the e-mail server defined metadata comprises at least one of a message subject, a message sender, a message recipient, a message time/date stamp, whether a message was replied to, whether a message was read, and whether a message was forwarded.

6. The communications system of claim 1 , wherein the first and second sets of metadata respectively comprise first and second sets of user defined metadata.

7. The communications system of claim 1 , wherein the aggregation server is also configured to send an updated set of mobile wireless communications device defined metadata to the e-mail server.

8. The communications system of claim 1 , wherein the pushed e-mail data comprises pushed e-mail messages.

9. The communications system of claim 1 , wherein the pushed e-mail data comprises pushed e-mail message search results.

10. An aggregation server for communicating with an e-mail server, the e-mail server being configured to store pushed e-mail data and metadata associated therewith, the aggregation server comprising:

a memory; and

a processor cooperating with the memory and configured to

download a first set of metadata of the pushed e-mail data,

generate a first set of hash values corresponding to the first set of metadata,

download a second set of metadata of the pushed e-mail data,

generate a second set of hash values corresponding to the second set of metadata, and

determine an updated set of metadata based upon a comparison of the first and second sets of hash values.

11. The aggregation server of claim 10 , wherein the processor is also configured to push the updated set of metadata to at least one mobile wireless communications device.

12. The aggregation server of claim 10 , wherein the e-mail server is also configured to store unpushed e-mail data; and wherein the processor is also configured to download the unpushed e-mail data, and push the unpushed e-mail data to at least one mobile wireless communications device.

13. The aggregation server of claim 10 , wherein the pushed e-mail data comprises pushed e-mail messages.

14. The aggregation server of claim 10 , wherein the pushed e-mail data comprises pushed e-mail message search results.

15. The aggregation server of claim 10 , wherein the processor is also configured to send an updated set of mobile wireless communications device defined metadata to the e-mail server.

16. A method of operating an aggregation server to communicate with an e-mail server configured to store pushed e-mail data and metadata associated therewith, the method comprising:

using a memory and a processor cooperating therewith to

download a first set of metadata of the pushed e-mail data,

generate a first set of hash values corresponding to the first set of metadata,

download a second set of metadata of the pushed e-mail data,

generate a second set of hash values corresponding to the second set of metadata, and

determine an updated set of metadata based upon a comparison of the first and second sets of hash values.

17. The method of claim 16 , further comprising using the processor and a transceiver coupled thereto to push the updated metadata to at least one mobile wireless communications device.

18. The method of claim 16 , wherein the first and second sets of metadata respectively comprise first and second sets of e-mail server defined metadata.

19. The method of claim 18 , wherein the e-mail server defined metadata comprises at least one of a message subject, a message sender, a message recipient, a message time/date stamp, whether a message was replied to, whether a message was read, and whether a message was forwarded.

20. The method of claim 16 , wherein the first and second sets of metadata respectively comprise first and second sets of user defined metadata.

21. The method of claim 16 , further using the processor and a transceiver coupled thereto to send an updated set of mobile wireless communications device defined metadata to the e-mail server.

22. The method of claim 16 , wherein the pushed e-mail data comprises pushed e-mail messages.

23. The method of claim 16 , wherein the pushed e-mail data comprises pushed e-mail message search results.