1. A computer-implemented method of providing speculative search results, comprising the steps of: receiving a search query from a client node; determining a search result for said search query; wherein determining the search result comprises performing an ordered search of different databases; wherein performing the ordered search of different databases comprises: performing, based on the search query, a first search that produces a first set of one or more search results, wherein performing the first search comprises searching a first set of one or more databases; determining whether the first set of one or more search results meet a relevance threshold, wherein the step of determining is based on relevance scores, assigned to documents in the first set of one or more search results, that reflect relevance between the first set of one or more search results and the search query; performing, based on the search query, a second search that produces a second set of one or more search results if and only if the first set of one or more search results do not meet the relevance threshold, wherein performing the second search comprises searching a second set of one or more databases, wherein the first set of one or more databases is different than the second set of one or more databases; determining whether the second set of search results meet the relevance threshold, wherein the step of determining whether the second set of search results meet the relevance threshold is based on relevance scores, assigned to documents in the second set of one or more search results, that reflect relevance between the second set of one or more search results and the search query; in response to determining that the second set of one or more search results meet the relevance threshold, (a) generating the search result from the second set of one or more search results, and (b) providing said search result to said client node, wherein said search result identifies at least one item that satisfies said search query; wherein the steps are performed on one or more computing devices.
1. A computer-implemented method of providing speculative search results, comprising the steps of: receiving a search query from a client node; determining a search result for said search query; wherein determining the search result comprises performing an ordered search of different databases; wherein performing the ordered search of different databases comprises: performing, based on the search query, a first search that produces a first set of one or more search results, wherein performing the first search comprises searching a first set of one or more databases; determining whether the first set of one or more search results meet a relevance threshold, wherein the step of determining is based on relevance scores, assigned to documents in the first set of one or more search results, that reflect relevance between the first set of one or more search results and the search query; performing, based on the search query, a second search that produces a second set of one or more search results if and only if the first set of one or more search results do not meet the relevance threshold, wherein performing the second search comprises searching a second set of one or more databases, wherein the first set of one or more databases is different than the second set of one or more databases; determining whether the second set of search results meet the relevance threshold, wherein the step of determining whether the second set of search results meet the relevance threshold is based on relevance scores, assigned to documents in the second set of one or more search results, that reflect relevance between the second set of one or more search results and the search query; in response to determining that the second set of one or more search results meet the relevance threshold, (a) generating the search result from the second set of one or more search results, and (b) providing said search result to said client node, wherein said search result identifies at least one item that satisfies said search query; wherein the steps are performed on one or more computing devices. 19. The method of claim 1 , wherein: the search query is not-yet-submitted; the search result is a speculative search result; determining the search result comprises determining the speculative search result for the not-yet-submitted search query prior to receiving an indication from said client node that said not-yet-submitted search query is completely formed; the first set of one or more search results is a first set of one or more speculative search results; the second set of one or more search results is a second set of one or more speculative search results; the method further comprising: receiving input that indicates that said search query is submitted, and performing a search based on said submitted search query.