21. A system for annotating webpage content, the system comprising: a computerized device communicatively coupled with a webpage server under control of a third party and with an annotations repository under control of an entity different from the third party, the computerized device including: a browser configured to perform first operations comprising, the first operations comprising receiving, from a user associated with the computerized device, a request to access a webpage being hosted by the webpage server, where the user is other than both the third party and the entity different from the third party, in response to said receiving from the user the request to access the webpage, requesting the webpage from the webpage server, and receiving a response from the webpage server including a current instance of the webpage, and the browser is further configured to perform second operations, the second operations comprising requesting, from the annotations repository in response to said receiving from the user the request to access the webpage, a collection of annotations made to the webpage by the user associated with the computerized device, the annotations collection being stored at the annotations repository, the annotations collection including one or more annotations relating to corresponding one or more portions of webpage content of the webpage, receiving a response from the annotations repository including the requested annotations collection, and concurrently displaying the current instance of the webpage received with the response from the webpage server and the annotations collection received with the response from the annotations repository, such that the one or more annotations included in the received annotations collection are overlaid on the corresponding one or more portions of the webpage content of the received current instance of the webpage.
21. A system for annotating webpage content, the system comprising: a computerized device communicatively coupled with a webpage server under control of a third party and with an annotations repository under control of an entity different from the third party, the computerized device including: a browser configured to perform first operations comprising, the first operations comprising receiving, from a user associated with the computerized device, a request to access a webpage being hosted by the webpage server, where the user is other than both the third party and the entity different from the third party, in response to said receiving from the user the request to access the webpage, requesting the webpage from the webpage server, and receiving a response from the webpage server including a current instance of the webpage, and the browser is further configured to perform second operations, the second operations comprising requesting, from the annotations repository in response to said receiving from the user the request to access the webpage, a collection of annotations made to the webpage by the user associated with the computerized device, the annotations collection being stored at the annotations repository, the annotations collection including one or more annotations relating to corresponding one or more portions of webpage content of the webpage, receiving a response from the annotations repository including the requested annotations collection, and concurrently displaying the current instance of the webpage received with the response from the webpage server and the annotations collection received with the response from the annotations repository, such that the one or more annotations included in the received annotations collection are overlaid on the corresponding one or more portions of the webpage content of the received current instance of the webpage. 39. The system of claim 21 , wherein the computerized device is further communicatively coupled with a second annotations repository under control of a second entity different from the third party, and the second operations further comprise informing the user associated with the computerized device of a second annotations collection being available at the second annotations repository, the second annotations collection having been authored by a second author different from the user associated with the computerized device, and being associated with the webpage, the second annotations collection including one or more annotations relating to corresponding one or more portions of webpage content of the webpage, receiving, from the user associated with the computerized device in response to said informing, a request to access the second annotations collection, in response to said receiving, from the user, of the request to access the second collection, requesting the second annotations collection from the second annotations repository, receiving a response from the second annotations repository including the second annotations collection, and concurrently displaying the current instance of the webpage received from the webpage server, the second annotations collection received from the second annotations repository and the annotations collection received from the annotations repository, such that the one or more annotations included in the initially received annotations collection and the one or more annotations included in the received second annotations collection are overlaid on the corresponding portions of the webpage content of the received current instance of the webpage.